VC UI: Add return to app panel UI

Given the information from VideoConferenceTrayController, renders a
ReturnToAppPanel that displays the information of currently running
media apps. This CL:
- Handles the data flow from the controller to the panel UI
- Defines all children classes and layouts of the panel, which shows all
the apps information and the aggregated summary at the top.

Screenshot:
- https://screenshot.googleplex.com/mi95mpsE7mx7Vn2
- https://screenshot.googleplex.com/8ZiB9bsd4Zkt3DA

Bug: b:253272945

Change-Id: Idf40f2f3b41b2e1e761a2db375758dc7a5bc5292
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4061999
Reviewed-by: Alex Newcomer <newcomer@chromium.org>
Reviewed-by: Ahmed Fakhry <afakhry@chromium.org>
Commit-Queue: Andre Le <leandre@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1087154}

ash/BUILD.gn

@@ -1953,8 +1953,8 @@ component("ash") {
     "system/video_conference/bubble/bubble_view.cc",
     "system/video_conference/bubble/bubble_view.h",
     "system/video_conference/bubble/bubble_view_ids.h",
-    "system/video_conference/bubble/return_to_app_button.cc",
+    "system/video_conference/bubble/return_to_app_panel.cc",
-    "system/video_conference/bubble/return_to_app_button.h",
+    "system/video_conference/bubble/return_to_app_panel.h",
     "system/video_conference/bubble/set_value_effects_view.cc",
     "system/video_conference/bubble/set_value_effects_view.h",
     "system/video_conference/bubble/toggle_effects_view.cc",
@@ -3217,6 +3217,7 @@ test("ash_unittests") {
     "system/update/update_notification_controller_unittest.cc",
     "system/usb_peripheral/usb_peripheral_notification_controller_unittest.cc",
     "system/video_conference/bubble/bubble_view_unittest.cc",
+    "system/video_conference/bubble/return_to_app_panel_unittest.cc",
     "system/video_conference/effects/video_conference_tray_effects_manager_unittest.cc",
     "system/video_conference/video_conference_tray_unittest.cc",
     "system/virtual_keyboard/virtual_keyboard_tray_unittest.cc",

ash/ash_strings.grd

@@ -1448,6 +1448,9 @@ Style notes:
       <message name="IDS_ASH_VIDEO_CONFERENCE_TOGGLE_BUBBLE_BUTTON_TOOLTIP" desc="The tooltip for the toggle bubble button in the video conference tray.">
         Camera and audio controls
       </message>
+      <message name="IDS_ASH_VIDEO_CONFERENCE_RETURN_TO_APP_SUMMARY_TEXT" desc="The summary text in the return to app panel of the video conference panel, specifying how many video conferencing apps are in used.">
+        Used by <ph name="APP_COUNT">$1<ex>2</ex></ph> apps
+      </message>
 
       <!-- Phone Hub tray-->
       <message name="IDS_ASH_PHONE_HUB_TRAY_ACCESSIBLE_NAME" desc="The accessible name of the Phone Hub tray bubble for screen readers.">

ash/ash_strings_grd/IDS_ASH_VIDEO_CONFERENCE_RETURN_TO_APP_SUMMARY_TEXT.png.sha1

@@ -0,0 +1 @@
+9c5553d20f01fb19fb379a165d5a9f1368505370

ash/system/video_conference/bubble/bubble_view.cc

@@ -6,7 +6,7 @@
 
 #include "ash/system/tray/tray_bubble_view.h"
 #include "ash/system/video_conference/bubble/bubble_view_ids.h"
-#include "ash/system/video_conference/bubble/return_to_app_button.h"
+#include "ash/system/video_conference/bubble/return_to_app_panel.h"
 #include "ash/system/video_conference/bubble/set_value_effects_view.h"
 #include "ash/system/video_conference/bubble/toggle_effects_view.h"
 #include "ash/system/video_conference/effects/video_conference_tray_effects_manager.h"
@@ -37,10 +37,10 @@ BubbleView::BubbleView(const InitParams& init_params,
   layout->SetMainAxisAlignment(views::LayoutAlignment::kCenter);
   layout->SetCrossAxisAlignment(views::LayoutAlignment::kStretch);
 
-  // `ReturnToAppButton` resides in the top-level layout and isn't part of the
+  // `ReturnToAppPanel` resides in the top-level layout and isn't part of the
   // scrollable area (that can't be added until the `BubbleView` officially has
   // a parent waidget).
-  AddChildView(std::make_unique<ReturnToAppButton>());
+  AddChildView(std::make_unique<ReturnToAppPanel>());
 }
 
 void BubbleView::AddedToWidget() {

ash/system/video_conference/bubble/return_to_app_button.cc

@@ -1,56 +0,0 @@
-// Copyright 2022 The Chromium Authors
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "ash/system/video_conference/bubble/return_to_app_button.h"
-
-#include "ash/resources/vector_icons/vector_icons.h"
-#include "ash/style/ash_color_id.h"
-#include "ash/system/video_conference/bubble/bubble_view_ids.h"
-#include "ui/base/models/image_model.h"
-#include "ui/views/background.h"
-#include "ui/views/border.h"
-#include "ui/views/controls/image_view.h"
-#include "ui/views/controls/label.h"
-#include "ui/views/layout/flex_layout.h"
-
-namespace ash::video_conference {
-
-namespace {
-
-const int kBorderInsetDimension = 10;
-const int kBackgroundRoundedRectRadius = 10;
-
-}  // namespace
-
-// TODO(b/253274599, b/253274147, b/253272945) Implement actual "return to app"
-// button functionality. This is a temporary placeholder for facilitating VC
-// bubble development.
-ReturnToAppButton::ReturnToAppButton() {
-  SetID(BubbleViewID::kReturnToApp);
-
-  views::FlexLayout* layout =
-      SetLayoutManager(std::make_unique<views::FlexLayout>());
-  layout->SetOrientation(views::LayoutOrientation::kHorizontal);
-  layout->SetMainAxisAlignment(views::LayoutAlignment::kCenter);
-  layout->SetCrossAxisAlignment(views::LayoutAlignment::kStretch);
-
-  auto camera = std::make_unique<views::ImageView>();
-  camera->SetImage(ui::ImageModel::FromVectorIcon(kPrivacyIndicatorsCameraIcon,
-                                                  kColorAshIconColorPrimary));
-  AddChildView(std::move(camera));
-
-  auto microphone = std::make_unique<views::ImageView>();
-  microphone->SetImage(ui::ImageModel::FromVectorIcon(
-      kPrivacyIndicatorsMicrophoneIcon, kColorAshIconColorPrimary));
-  AddChildView(std::move(microphone));
-
-  AddChildView(std::make_unique<views::Label>(u"Meet"));
-
-  SetBorder(views::CreateEmptyBorder(
-      gfx::Insets::VH(kBorderInsetDimension, kBorderInsetDimension)));
-  SetBackground(views::CreateRoundedRectBackground(
-      gfx::kGoogleBlue800, kBackgroundRoundedRectRadius));
-}
-
-}  // namespace ash::video_conference

ash/system/video_conference/bubble/return_to_app_button.h

@@ -1,26 +0,0 @@
-// Copyright 2022 The Chromium Authors
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef ASH_SYSTEM_VIDEO_CONFERENCE_BUBBLE_RETURN_TO_APP_BUTTON_H_
-#define ASH_SYSTEM_VIDEO_CONFERENCE_BUBBLE_RETURN_TO_APP_BUTTON_H_
-
-#include "ui/views/view.h"
-
-namespace ash::video_conference {
-
-// The "return to app" button that resides in the video conference bubble. The
-// user selects from a list of apps that are actively capturing audio/video
-// and/or sharing the screen, and the selected app is brought to the top and
-// focused.
-class ReturnToAppButton : public views::View {
- public:
-  ReturnToAppButton();
-  ReturnToAppButton(const ReturnToAppButton&) = delete;
-  ReturnToAppButton& operator=(const ReturnToAppButton&) = delete;
-  ~ReturnToAppButton() override = default;
-};
-
-}  // namespace ash::video_conference
-
-#endif  // ASH_SYSTEM_VIDEO_CONFERENCE_BUBBLE_RETURN_TO_APP_BUTTON_H_

ash/system/video_conference/bubble/return_to_app_panel.cc

@@ -0,0 +1,171 @@
+// Copyright 2022 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "ash/system/video_conference/bubble/return_to_app_panel.h"
+
+#include <memory>
+
+#include "ash/resources/vector_icons/vector_icons.h"
+#include "ash/strings/grit/ash_strings.h"
+#include "ash/style/ash_color_id.h"
+#include "ash/system/video_conference/bubble/bubble_view_ids.h"
+#include "ash/system/video_conference/video_conference_tray_controller.h"
+#include "base/strings/utf_string_conversions.h"
+#include "chromeos/crosapi/mojom/video_conference.mojom.h"
+#include "ui/base/l10n/l10n_util.h"
+#include "ui/base/models/image_model.h"
+#include "ui/chromeos/styles/cros_tokens_color_mappings.h"
+#include "ui/views/background.h"
+#include "ui/views/border.h"
+#include "ui/views/controls/image_view.h"
+#include "ui/views/controls/label.h"
+#include "ui/views/layout/flex_layout.h"
+
+namespace ash::video_conference {
+
+namespace {
+
+const int kReturnToAppPanelRadius = 16;
+const int kReturnToAppPanelSpacing = 8;
+const int kReturnToAppButtonSpacing = 12;
+const int kReturnToAppButtonIconsSpacing = 2;
+
+// Creates a view containing camera, microphone, and screen share icons that
+// shows capturing state of a media app.
+std::unique_ptr<views::View> CreateReturnToAppIconsContainer(
+    bool is_capturing_camera,
+    bool is_capturing_microphone,
+    bool is_capturing_screen) {
+  auto container = std::make_unique<views::View>();
+  container->SetLayoutManager(std::make_unique<views::FlexLayout>())
+      ->SetOrientation(views::LayoutOrientation::kHorizontal)
+      .SetMainAxisAlignment(views::LayoutAlignment::kCenter)
+      .SetCrossAxisAlignment(views::LayoutAlignment::kStretch)
+      .SetDefault(views::kMarginsKey,
+                  gfx::Insets::TLBR(0, kReturnToAppButtonIconsSpacing / 2, 0,
+                                    kReturnToAppButtonIconsSpacing / 2));
+
+  if (is_capturing_camera) {
+    auto camera_icon = std::make_unique<views::ImageView>();
+    camera_icon->SetImage(ui::ImageModel::FromVectorIcon(
+        kPrivacyIndicatorsCameraIcon, cros_tokens::kCrosSysPositive));
+    container->AddChildView(std::move(camera_icon));
+  }
+
+  if (is_capturing_microphone) {
+    auto microphone_icon = std::make_unique<views::ImageView>();
+    microphone_icon->SetImage(ui::ImageModel::FromVectorIcon(
+        kPrivacyIndicatorsMicrophoneIcon, cros_tokens::kCrosSysPositive));
+    container->AddChildView(std::move(microphone_icon));
+  }
+
+  if (is_capturing_screen) {
+    auto screen_share_icon = std::make_unique<views::ImageView>();
+    screen_share_icon->SetImage(ui::ImageModel::FromVectorIcon(
+        kPrivacyIndicatorsScreenShareIcon, cros_tokens::kCrosSysPositive));
+    container->AddChildView(std::move(screen_share_icon));
+  }
+
+  return container;
+}
+
+// Gets the display text representing a media app shown in the return to app
+// panel.
+std::u16string GetMediaAppDisplayText(
+    mojo::StructPtr<crosapi::mojom::VideoConferenceMediaAppInfo>& media_app) {
+  // Displays the url if it is valid. Otherwise, display app title.
+  auto url = media_app->url;
+  return url && url->is_valid() ? base::UTF8ToUTF16(url->GetContent())
+                                : media_app->title;
+}
+
+}  // namespace
+
+// -----------------------------------------------------------------------------
+// ReturnToAppButton:
+
+ReturnToAppButton::ReturnToAppButton(bool is_capturing_camera,
+                                     bool is_capturing_microphone,
+                                     bool is_capturing_screen,
+                                     const std::u16string& display_text)
+    : is_capturing_camera_(is_capturing_camera),
+      is_capturing_microphone_(is_capturing_microphone),
+      is_capturing_screen_(is_capturing_screen) {
+  SetLayoutManager(std::make_unique<views::FlexLayout>())
+      ->SetOrientation(views::LayoutOrientation::kHorizontal)
+      .SetMainAxisAlignment(views::LayoutAlignment::kCenter)
+      .SetCrossAxisAlignment(views::LayoutAlignment::kStretch)
+      .SetDefault(views::kMarginsKey,
+                  gfx::Insets::TLBR(0, kReturnToAppButtonSpacing / 2, 0,
+                                    kReturnToAppButtonSpacing / 2));
+
+  AddChildView(CreateReturnToAppIconsContainer(
+      is_capturing_camera, is_capturing_microphone, is_capturing_screen));
+
+  label_ = AddChildView(std::make_unique<views::Label>(display_text));
+}
+
+// -----------------------------------------------------------------------------
+// ReturnToAppPanel:
+
+ReturnToAppPanel::ReturnToAppPanel() {
+  SetID(BubbleViewID::kReturnToApp);
+
+  SetLayoutManager(std::make_unique<views::FlexLayout>())
+      ->SetOrientation(views::LayoutOrientation::kVertical)
+      .SetMainAxisAlignment(views::LayoutAlignment::kCenter)
+      .SetCrossAxisAlignment(views::LayoutAlignment::kStretch)
+      .SetDefault(views::kMarginsKey,
+                  gfx::Insets::TLBR(0, 0, kReturnToAppPanelSpacing, 0))
+      .SetInteriorMargin(gfx::Insets::TLBR(12, 0, 0, 0));
+
+  // Add running media apps buttons to the panel.
+  VideoConferenceTrayController::Get()->GetMediaApps(base::BindOnce(
+      &ReturnToAppPanel::AddButtonsToPanel, weak_ptr_factory_.GetWeakPtr()));
+
+  SetBackground(views::CreateThemedRoundedRectBackground(
+      cros_tokens::kCrosSysSystemOnBase, kReturnToAppPanelRadius));
+}
+
+ReturnToAppPanel::~ReturnToAppPanel() = default;
+
+void ReturnToAppPanel::AddButtonsToPanel(MediaApps apps) {
+  if (apps.size() < 1) {
+    SetVisible(false);
+    return;
+  }
+
+  if (apps.size() == 1) {
+    auto& app = apps.front();
+    AddChildView(std::make_unique<ReturnToAppButton>(
+        app->is_capturing_camera, app->is_capturing_microphone,
+        app->is_capturing_screen, GetMediaAppDisplayText(app)));
+    return;
+  }
+
+  bool any_apps_capturing_camera = false;
+  bool any_apps_capturing_microphone = false;
+  bool any_apps_capturing_screen = false;
+
+  for (auto& app : apps) {
+    AddChildView(std::make_unique<ReturnToAppButton>(
+        app->is_capturing_camera, app->is_capturing_microphone,
+        app->is_capturing_screen, GetMediaAppDisplayText(app)));
+
+    any_apps_capturing_camera |= app->is_capturing_camera;
+    any_apps_capturing_microphone |= app->is_capturing_microphone;
+    any_apps_capturing_screen |= app->is_capturing_screen;
+  }
+
+  auto summary_text = l10n_util::GetStringFUTF16Int(
+      IDS_ASH_VIDEO_CONFERENCE_RETURN_TO_APP_SUMMARY_TEXT,
+      static_cast<int>(apps.size()));
+
+  AddChildViewAt(std::make_unique<ReturnToAppButton>(
+                     any_apps_capturing_camera, any_apps_capturing_microphone,
+                     any_apps_capturing_screen, summary_text),
+                 0);
+}
+
+}  // namespace ash::video_conference

ash/system/video_conference/bubble/return_to_app_panel.h

@@ -0,0 +1,76 @@
+// Copyright 2022 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef ASH_SYSTEM_VIDEO_CONFERENCE_BUBBLE_RETURN_TO_APP_PANEL_H_
+#define ASH_SYSTEM_VIDEO_CONFERENCE_BUBBLE_RETURN_TO_APP_PANEL_H_
+
+#include <string>
+
+#include "ash/ash_export.h"
+#include "base/memory/weak_ptr.h"
+#include "chromeos/crosapi/mojom/video_conference.mojom-forward.h"
+#include "ui/views/view.h"
+
+namespace views {
+class Label;
+}  // namespace views
+
+namespace ash::video_conference {
+
+using MediaApps = std::vector<crosapi::mojom::VideoConferenceMediaAppInfoPtr>;
+
+// The "return to app" button that resides within the "return to app" panel,
+// showing information of a particular running media app. Clicking on this
+// button will take users to the app.
+class ASH_EXPORT ReturnToAppButton : public views::View {
+ public:
+  ReturnToAppButton(bool is_capturing_camera,
+                    bool is_capturing_microphone,
+                    bool is_capturing_screen,
+                    const std::u16string& display_text);
+
+  ReturnToAppButton(const ReturnToAppButton&) = delete;
+  ReturnToAppButton& operator=(const ReturnToAppButton&) = delete;
+
+  ~ReturnToAppButton() override = default;
+
+  bool is_capturing_camera() const { return is_capturing_camera_; }
+  bool is_capturing_microphone() const { return is_capturing_microphone_; }
+  bool is_capturing_screen() const { return is_capturing_screen_; }
+
+  views::Label* label() { return label_; }
+
+ private:
+  // Indicates if the running app is using camera, microphone, or screen
+  // sharing.
+  const bool is_capturing_camera_;
+  const bool is_capturing_microphone_;
+  const bool is_capturing_screen_;
+
+  // Label showing the url or name of the running app. Owned by the views
+  // hierarchy.
+  views::Label* label_ = nullptr;
+};
+
+// The "return to app" panel that resides in the video conference bubble. The
+// user selects from a list of apps that are actively capturing audio/video
+// and/or sharing the screen, and the selected app is brought to the top and
+// focused.
+class ASH_EXPORT ReturnToAppPanel : public views::View {
+ public:
+  ReturnToAppPanel();
+  ReturnToAppPanel(const ReturnToAppPanel&) = delete;
+  ReturnToAppPanel& operator=(const ReturnToAppPanel&) = delete;
+  ~ReturnToAppPanel() override;
+
+ private:
+  // Used by the ctor to add `ReturnToAppButton`(s) to the panel.
+  void AddButtonsToPanel(MediaApps apps);
+
+  base::WeakPtrFactory<ReturnToAppPanel> weak_ptr_factory_{this};
+};
+
+}  // namespace ash::video_conference
+
+#endif  // ASH_SYSTEM_VIDEO_CONFERENCE_BUBBLE_RETURN_TO_APP_PANEL_H_

ash/system/video_conference/bubble/return_to_app_panel_unittest.cc

@@ -0,0 +1,158 @@
+// Copyright 2022 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "ash/system/video_conference/bubble/return_to_app_panel.h"
+#include <memory>
+
+#include "ash/constants/ash_features.h"
+#include "ash/strings/grit/ash_strings.h"
+#include "ash/system/video_conference/fake_video_conference_tray_controller.h"
+#include "ash/test/ash_test_base.h"
+#include "base/test/scoped_feature_list.h"
+#include "chromeos/crosapi/mojom/video_conference.mojom.h"
+#include "ui/base/l10n/l10n_util.h"
+#include "ui/views/controls/label.h"
+
+namespace {
+
+// Verifies the information of `ReturnToAppButton`.
+void VerifyReturnToAppButtonInfo(
+    ash::video_conference::ReturnToAppButton* button,
+    bool is_capturing_camera,
+    bool is_capturing_microphone,
+    bool is_capturing_screen,
+    const std::u16string& display_text) {
+  EXPECT_EQ(is_capturing_camera, button->is_capturing_camera());
+  EXPECT_EQ(is_capturing_microphone, button->is_capturing_microphone());
+  EXPECT_EQ(is_capturing_screen, button->is_capturing_screen());
+  EXPECT_EQ(display_text, button->label()->GetText());
+}
+
+// Used for verifying displayed url.
+const std::string kGoogleMeetTestUrl = "https://meet.google.com/abc-xyz/ab-123";
+const std::u16string kExpectedGoogleMeetDisplayedUrl =
+    u"meet.google.com/abc-xyz/ab-123";
+
+}  // namespace
+
+namespace ash::video_conference {
+
+class ReturnToAppPanelTest : public AshTestBase {
+ public:
+  ReturnToAppPanelTest() = default;
+  ReturnToAppPanelTest(const ReturnToAppPanelTest&) = delete;
+  ReturnToAppPanelTest& operator=(const ReturnToAppPanelTest&) = delete;
+  ~ReturnToAppPanelTest() override = default;
+
+  // AshTestBase:
+  void SetUp() override {
+    scoped_feature_list_.InitAndEnableFeature(features::kVcControlsUi);
+
+    // Here we have to create the global instance of `CrasAudioHandler` before
+    // `FakeVideoConferenceTrayController`, so we do it here and not do it in
+    // `AshTestBase`.
+    CrasAudioClient::InitializeFake();
+    CrasAudioHandler::InitializeForTesting();
+
+    // Instantiates a fake controller (the real one is created in
+    // ChromeBrowserMainExtraPartsAsh::PreProfileInit() which is not called in
+    // ash unit tests).
+    controller_ = std::make_unique<FakeVideoConferenceTrayController>();
+
+    set_create_global_cras_audio_handler(false);
+    AshTestBase::SetUp();
+  }
+
+  void TearDown() override {
+    AshTestBase::TearDown();
+    controller_.reset();
+    CrasAudioHandler::Shutdown();
+    CrasAudioClient::Shutdown();
+  }
+
+  FakeVideoConferenceTrayController* controller() { return controller_.get(); }
+
+ private:
+  base::test::ScopedFeatureList scoped_feature_list_;
+  std::unique_ptr<FakeVideoConferenceTrayController> controller_;
+};
+
+TEST_F(ReturnToAppPanelTest, NoApp) {
+  controller()->ClearMediaApps();
+
+  // The view should not be visible when there's no app.
+  auto return_to_app_panel = std::make_unique<ReturnToAppPanel>();
+  EXPECT_FALSE(return_to_app_panel->GetVisible());
+}
+
+TEST_F(ReturnToAppPanelTest, OneApp) {
+  bool is_capturing_camera = true;
+  bool is_capturing_microphone = false;
+  bool is_capturing_screen = false;
+  controller()->ClearMediaApps();
+  controller()->AddMediaApp(crosapi::mojom::VideoConferenceMediaAppInfo::New(
+      /*id=*/base::UnguessableToken::Create(),
+      /*last_activity_time=*/base::Time::Now(), is_capturing_camera,
+      is_capturing_microphone, is_capturing_screen, /*title=*/u"Google Meet",
+      /*url=*/GURL(kGoogleMeetTestUrl)));
+
+  // There should be one child representing the only one running media app.
+  auto return_to_app_panel = std::make_unique<ReturnToAppPanel>();
+  EXPECT_EQ(1u, return_to_app_panel->children().size());
+
+  auto* app_button =
+      static_cast<ReturnToAppButton*>(return_to_app_panel->children().front());
+  VerifyReturnToAppButtonInfo(app_button, is_capturing_camera,
+                              is_capturing_microphone, is_capturing_screen,
+                              kExpectedGoogleMeetDisplayedUrl);
+}
+
+TEST_F(ReturnToAppPanelTest, MultipleApps) {
+  controller()->ClearMediaApps();
+  controller()->AddMediaApp(crosapi::mojom::VideoConferenceMediaAppInfo::New(
+      /*id=*/base::UnguessableToken::Create(),
+      /*last_activity_time=*/base::Time::Now(),
+      /*is_capturing_camera=*/true, /*is_capturing_microphone=*/false,
+      /*is_capturing_screen=*/false, /*title=*/u"Google Meet",
+      /*url=*/GURL(kGoogleMeetTestUrl)));
+  controller()->AddMediaApp(crosapi::mojom::VideoConferenceMediaAppInfo::New(
+      /*id=*/base::UnguessableToken::Create(),
+      /*last_activity_time=*/base::Time::Now(),
+      /*is_capturing_camera=*/false, /*is_capturing_microphone=*/true,
+      /*is_capturing_screen=*/true, /*title=*/u"Zoom",
+      /*url=*/absl::nullopt));
+
+  // There should be three children, one representing the summary row and two
+  // for two running media apps.
+  auto return_to_app_panel = std::make_unique<ReturnToAppPanel>();
+  EXPECT_EQ(3u, return_to_app_panel->children().size());
+
+  // The first row should be the summary row, representing the state of
+  // capturing from all apps and showing that 2 apps are running.
+  auto* summary_row =
+      static_cast<ReturnToAppButton*>(return_to_app_panel->children().front());
+  VerifyReturnToAppButtonInfo(
+      summary_row, /*is_capturing_camera=*/true,
+      /*is_capturing_microphone=*/true,
+      /*is_capturing_screen=*/true,
+      l10n_util::GetStringFUTF16Int(
+          IDS_ASH_VIDEO_CONFERENCE_RETURN_TO_APP_SUMMARY_TEXT, 2));
+
+  // Verify the next 2 rows, representing the 2 running apps.
+  auto* first_app_row =
+      static_cast<ReturnToAppButton*>(return_to_app_panel->children()[1]);
+  VerifyReturnToAppButtonInfo(first_app_row, /*is_capturing_camera=*/true,
+                              /*is_capturing_microphone=*/false,
+                              /*is_capturing_screen=*/false,
+                              kExpectedGoogleMeetDisplayedUrl);
+
+  // If the url is not provided, the button should display the app title.
+  auto* second_app_row =
+      static_cast<ReturnToAppButton*>(return_to_app_panel->children()[2]);
+  VerifyReturnToAppButtonInfo(second_app_row, /*is_capturing_camera=*/false,
+                              /*is_capturing_microphone=*/true,
+                              /*is_capturing_screen=*/true, u"Zoom");
+}
+
+}  // namespace ash::video_conference

ash/system/video_conference/fake_video_conference_tray_controller.cc

@@ -5,15 +5,32 @@
 #include "ash/system/video_conference/fake_video_conference_tray_controller.h"
 
 #include "ash/system/video_conference/effects/fake_video_conference_effects.h"
+#include "ash/system/video_conference/video_conference_tray_controller.h"
+#include "base/functional/callback.h"
 #include "chromeos/ash/components/audio/cras_audio_handler.h"
+#include "chromeos/crosapi/mojom/video_conference.mojom.h"
 #include "media/capture/video/chromeos/mojom/cros_camera_service.mojom-shared.h"
+#include "url/gurl.h"
 
 namespace ash {
 
 FakeVideoConferenceTrayController::FakeVideoConferenceTrayController()
     : effect_repository_(
           std::make_unique<fake_video_conference::EffectRepository>(
-              /*controller=*/this)) {}
+              /*controller=*/this)) {
+  AddMediaApp(crosapi::mojom::VideoConferenceMediaAppInfo::New(
+      /*id=*/base::UnguessableToken::Create(),
+      /*last_activity_time=*/base::Time::Now(),
+      /*is_capturing_camera=*/true, /*is_capturing_microphone=*/false,
+      /*is_capturing_screen=*/false, /*title=*/u"Google Meet",
+      /*url=*/GURL("https://meet.google.com/abc-xyz/ab-123")));
+  AddMediaApp(crosapi::mojom::VideoConferenceMediaAppInfo::New(
+      /*id=*/base::UnguessableToken::Create(),
+      /*last_activity_time=*/base::Time::Now(),
+      /*is_capturing_camera=*/false, /*is_capturing_microphone=*/true,
+      /*is_capturing_screen=*/true, /*title=*/u"Zoom",
+      /*url=*/absl::nullopt));
+}
 
 FakeVideoConferenceTrayController::~FakeVideoConferenceTrayController() {
   effect_repository_.reset();
@@ -32,4 +49,22 @@ void FakeVideoConferenceTrayController::SetMicrophoneMuted(bool muted) {
                      CrasAudioHandler::InputMuteChangeMethod::kKeyboardButton);
 }
 
+void FakeVideoConferenceTrayController::GetMediaApps(
+    base::OnceCallback<void(MediaApps)> ui_callback) {
+  MediaApps apps;
+  for (auto& app : media_apps_) {
+    apps.push_back(app->Clone());
+  }
+  std::move(ui_callback).Run(std::move(apps));
+}
+
+void FakeVideoConferenceTrayController::AddMediaApp(
+    crosapi::mojom::VideoConferenceMediaAppInfoPtr media_app) {
+  media_apps_.push_back(std::move(media_app));
+}
+
+void FakeVideoConferenceTrayController::ClearMediaApps() {
+  media_apps_.clear();
+}
+
 }  // namespace ash

ash/system/video_conference/fake_video_conference_tray_controller.h

@@ -31,11 +31,19 @@ class ASH_EXPORT FakeVideoConferenceTrayController
   // VideoConferenceTrayController:
   void SetCameraMuted(bool muted) override;
   void SetMicrophoneMuted(bool muted) override;
+  void GetMediaApps(base::OnceCallback<void(MediaApps)> ui_callback) override;
+
+  // Adds or clears media app(s) in `media_apps_`.
+  void AddMediaApp(crosapi::mojom::VideoConferenceMediaAppInfoPtr media_app);
+  void ClearMediaApps();
 
   bool camera_muted() { return camera_muted_; }
   bool microphone_muted() { return microphone_muted_; }
 
  private:
+  // A vector containing all currently running media apps. Used for testing.
+  MediaApps media_apps_;
+
   // Indicates whether camera/microphone is muted.
   bool camera_muted_ = false;
   bool microphone_muted_ = false;

ash/system/video_conference/video_conference_tray_controller.h

@@ -15,6 +15,8 @@
 
 namespace ash {
 
+using MediaApps = std::vector<crosapi::mojom::VideoConferenceMediaAppInfoPtr>;
+
 // Controller that will act as a "bridge" between VC apps management and the VC
 // UI layers. The singleton instance is constructed immediately before and
 // destructed immediately after the UI, so any code that keeps a reference to
@@ -69,6 +71,11 @@ class ASH_EXPORT VideoConferenceTrayController
   // Sets the state for microphone mute. Virtual for testing/mocking.
   virtual void SetMicrophoneMuted(bool muted) = 0;
 
+  // Returns asynchronously a vector of media apps that will be displayed in the
+  // "Return to app" panel of the bubble. Virtual for testing/mocking.
+  virtual void GetMediaApps(
+      base::OnceCallback<void(MediaApps)> ui_callback) = 0;
+
   // Updates the tray UI with the given `VideoConferenceMediaState`.
   void UpdateWithMediaState(VideoConferenceMediaState state);
 

chrome/browser/ash/video_conference/video_conference_tray_controller_impl.cc

@@ -7,6 +7,9 @@
 #include "ash/constants/ash_pref_names.h"
 #include "ash/session/session_controller_impl.h"
 #include "ash/shell.h"
+#include "chrome/browser/ash/crosapi/crosapi_ash.h"
+#include "chrome/browser/ash/crosapi/crosapi_manager.h"
+#include "chrome/browser/ash/video_conference/video_conference_manager_ash.h"
 #include "components/prefs/pref_service.h"
 
 namespace ash {
@@ -35,4 +38,12 @@ void VideoConferenceTrayControllerImpl::SetMicrophoneMuted(bool muted) {
   pref_service->SetBoolean(prefs::kUserMicrophoneAllowed, !muted);
 }
 
+void VideoConferenceTrayControllerImpl::GetMediaApps(
+    base::OnceCallback<void(MediaApps)> ui_callback) {
+  crosapi::CrosapiManager::Get()
+      ->crosapi_ash()
+      ->video_conference_manager_ash()
+      ->GetMediaApps(std::move(ui_callback));
+}
+
 }  // namespace ash

chrome/browser/ash/video_conference/video_conference_tray_controller_impl.h

@@ -24,6 +24,7 @@ class VideoConferenceTrayControllerImpl : public VideoConferenceTrayController {
   // VideoConferenceTrayController:
   void SetCameraMuted(bool muted) override;
   void SetMicrophoneMuted(bool muted) override;
+  void GetMediaApps(base::OnceCallback<void(MediaApps)> ui_callback) override;
 };
 
 }  // namespace ash