[CodeHealth] Clean up WebContentsCaptureHiDPI feature

The feature was launched in M114, cleaning up the code.
Note: the cleanup was attempted in the past in crrev.com/c/4977161,
but was reverted due to MSAN failures. Some tests were reworked or
removed in the past year, and now there are no failures when I run
the same linux_chromium_chromeos_msan_rel_ng bot, so the cleanup
can be landed again.

Bug: 356624220
Change-Id: Ie8c22105eea8a8f6d5e87cee7daba14f3f324fc5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6120408
Reviewed-by: Thomas Guilbert <tguilbert@chromium.org>
Commit-Queue: Maria Kazinova <kazinova@google.com>
Reviewed-by: Alex Moshchuk <alexmos@chromium.org>
Reviewed-by: Jordan Bayles <jophba@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1401376}

chrome/browser/media/webrtc/webrtc_getdisplaymedia_browsertest.cc

@@ -128,8 +128,7 @@ struct TestConfigForFakeUI {
   const char* display_surface;
 };
 
-struct TestConfigForHiDpi {
-  bool enable_hidpi;
+struct TestConfigForMediaResolution {
   int constraint_width;
   int constraint_height;
 };
@@ -923,29 +922,21 @@ IN_PROC_BROWSER_TEST_P(GetDisplayMediaVideoTrackBrowserTest, RunCombinedTest) {
     !(defined(MEMORY_SANITIZER) || defined(ADDRESS_SANITIZER))
 class GetDisplayMediaHiDpiBrowserTest
     : public WebRtcTestBase,
-      public testing::WithParamInterface<TestConfigForHiDpi> {
+      public testing::WithParamInterface<TestConfigForMediaResolution> {
  public:
   GetDisplayMediaHiDpiBrowserTest() : test_config_(GetParam()) {}
 
   // The browser window size must be consistent with the
-  // INSTANTIATE_TEST_SUITE_P TestConfigForHiDpi configurations below. See the
-  // comments there for more details.
+  // INSTANTIATE_TEST_SUITE_P TestConfigForMediaResolution configurations below.
+  // See the comments there for more details.
   static constexpr int kBrowserWindowWidth = 800;
   static constexpr int kBrowserWindowHeight = 600;
 
-  bool enable_hidpi() const { return test_config_.enable_hidpi; }
   int constraint_width() const { return test_config_.constraint_width; }
   int constraint_height() const { return test_config_.constraint_height; }
 
   void SetUpInProcessBrowserTestFixture() override {
-    if (enable_hidpi()) {
-      feature_list_.InitAndEnableFeature(media::kWebContentsCaptureHiDpi);
-    } else {
-      feature_list_.InitAndDisableFeature(media::kWebContentsCaptureHiDpi);
-    }
-
     WebRtcTestBase::SetUpInProcessBrowserTestFixture();
-
     DetectErrorsInJavaScript();
   }
 
@@ -1012,8 +1003,7 @@ class GetDisplayMediaHiDpiBrowserTest
         .ExtractString();
   }
 
-  base::test::ScopedFeatureList feature_list_;
-  const TestConfigForHiDpi test_config_;
+  const TestConfigForMediaResolution test_config_;
   raw_ptr<content::WebContents, AcrossTasksDanglingUntriaged> tab_ = nullptr;
 };
 
@@ -1048,10 +1038,8 @@ IN_PROC_BROWSER_TEST_P(GetDisplayMediaHiDpiBrowserTest, Capture) {
   WaitForVideoToPlay(Tab());
 
   // If the video size is higher resolution than the browser window
-  // size, expect that HiDPI mode should be active. This requires
-  // the feature to be enabled.
-  bool expect_hidpi = enable_hidpi() &&
-                      constraint_width() > kBrowserWindowWidth &&
+  // size, expect that HiDPI mode should be active.
+  bool expect_hidpi = constraint_width() > kBrowserWindowWidth &&
                       constraint_height() > kBrowserWindowHeight;
 
   double device_pixel_ratio = GetDevicePixelRatio();
@@ -1071,15 +1059,10 @@ INSTANTIATE_TEST_SUITE_P(
     // (cf. kBrowserWindowWidth and kBrowserWindowHeight in
     // GetDisplayMediaHiDpiBrowserTest above), and the large sizes must be
     // significantly larger than the browser window size.
-    Values(TestConfigForHiDpi{/*enable_hidpi=*/false,
-                              /*constraint_width=*/3840,
-                              /*constraint_height=*/2160},
-           TestConfigForHiDpi{/*enable_hidpi=*/true,
-                              /*constraint_width=*/640,
-                              /*constraint_height=*/480},
-           TestConfigForHiDpi{/*enable_hidpi=*/true,
-                              /*constraint_width=*/3840,
-                              /*constraint_height=*/2160}));
+    Values(TestConfigForMediaResolution{/*constraint_width=*/640,
+                                        /*constraint_height=*/480},
+           TestConfigForMediaResolution{/*constraint_width=*/3840,
+                                        /*constraint_height=*/2160}));
 #endif
 
 class GetDisplayMediaChangeSourceBrowserTest

content/browser/media/capture/web_contents_auto_scaler_unittest.cc

@@ -38,10 +38,6 @@ class WebContentsAutoScalerTest : public ::testing::Test {
   WebContentsAutoScalerTest() = default;
   ~WebContentsAutoScalerTest() override = default;
 
-  void SetUp() override {
-    feature_list_.InitAndEnableFeature(media::kWebContentsCaptureHiDpi);
-  }
-
   void CreateAutoScaler(const gfx::Size& capture_size) {
     scaler_ = std::make_unique<WebContentsAutoScaler>(delegate_, capture_size);
   }

content/browser/media/capture/web_contents_frame_tracker.cc

@@ -29,7 +29,6 @@
 #include "content/public/browser/web_contents.h"
 #include "content/public/browser/web_contents_media_capture_id.h"
 #include "content/public/browser/web_contents_observer.h"
-#include "media/base/media_switches.h"
 #include "media/base/video_util.h"
 #include "media/capture/mojom/video_capture_types.mojom.h"
 #include "media/capture/video_capture_types.h"
@@ -164,7 +163,6 @@ void WebContentsFrameTracker::WillStartCapturingWebContents(
 
   capture_size_ = capture_size;
   if (is_high_dpi_enabled &&
-      base::FeatureList::IsEnabled(media::kWebContentsCaptureHiDpi) &&
       !GpuDataManagerImpl::GetInstance()->IsGpuCompositingDisabled()) {
     auto_scaler_ =
         std::make_unique<WebContentsAutoScaler>(*context_, capture_size);

content/browser/media/capture/web_contents_video_capture_device_browsertest.cc

@@ -26,7 +26,6 @@
 #include "content/public/browser/web_contents.h"
 #include "content/public/test/browser_test.h"
 #include "content/shell/browser/shell.h"
-#include "media/base/media_switches.h"
 #include "media/base/video_frame.h"
 #include "media/base/video_types.h"
 #include "media/base/video_util.h"
@@ -52,10 +51,7 @@ class WebContentsVideoCaptureDeviceBrowserTest
     : public ContentCaptureDeviceBrowserTestBase,
       public FrameTestUtil {
  public:
-  WebContentsVideoCaptureDeviceBrowserTest() {
-    // TODO(https://crbug.com/1324757): tests should work with HiDPI enabled.
-    scoped_feature_list_.InitAndDisableFeature(media::kWebContentsCaptureHiDpi);
-  }
+  WebContentsVideoCaptureDeviceBrowserTest() = default;
 
   WebContentsVideoCaptureDeviceBrowserTest(
       const WebContentsVideoCaptureDeviceBrowserTest&) = delete;

content/browser/renderer_host/render_widget_host_view_mac.h

@@ -565,6 +565,13 @@ class CONTENT_EXPORT RenderWidgetHostViewMac
 
   void UpdateWindowsNow();
 
+  // For HiDPI capture mode, adjust the device scale factor to render the
+  // contents at a higher pixel density when scale_override_for_capture_ > 1.0.
+  // The first boolean returns true if any of the ScreenInfo elements in
+  // `screen_infos_` was changed. The second boolean returns true if the current
+  // ScreenInfo element was changed.
+  std::pair<bool, bool> MaybeUpdateScreenInfosForHiDPI();
+
   // Interface through which the NSView is to be manipulated. This points either
   // to |in_process_ns_view_bridge_| or to |remote_ns_view_|.
   raw_ptr<remote_cocoa::mojom::RenderWidgetHostNSView> ns_view_ = nullptr;

content/browser/renderer_host/render_widget_host_view_mac.mm

@@ -876,29 +876,9 @@ void RenderWidgetHostViewMac::UpdateScreenInfo() {
     new_screen_infos_from_shim_.reset();
   }
 
-  if (base::FeatureList::IsEnabled(media::kWebContentsCaptureHiDpi)) {
-    // If HiDPI capture mode is active, adjust the device scale factor to
-    // increase the rendered pixel count. |new_screen_infos| always contains
-    // the unmodified original values for the display, and a copy of it is
-    // saved in |screen_infos_|, with a modification applied if applicable.
-    // When HiDPI mode is turned off (the scale override is 1.0), the original
-    // |new_screen_infos| value gets copied unchanged to |screen_infos_|.
-    display::ScreenInfos new_screen_infos = original_screen_infos_;
-    const float old_device_scale_factor =
-        new_screen_infos.current().device_scale_factor;
-    new_screen_infos.mutable_current().device_scale_factor =
-        old_device_scale_factor * scale_override_for_capture_;
-    if (screen_infos_ != new_screen_infos) {
-      DVLOG(1) << __func__ << ": Overriding device_scale_factor from "
-               << old_device_scale_factor << " to "
-               << new_screen_infos.current().device_scale_factor
-               << " for capture.";
-      any_display_changed = true;
-      current_display_changed |=
-          new_screen_infos.current() != screen_infos_.current();
-      screen_infos_ = new_screen_infos;
-    }
-  }
+  std::pair<bool, bool> was_updated = MaybeUpdateScreenInfosForHiDPI();
+  any_display_changed |= was_updated.first;
+  current_display_changed |= was_updated.second;
 
   bool dip_size_changed = view_bounds_in_window_dip_.size() !=
                           browser_compositor_->GetRendererSize();
@@ -2428,6 +2408,32 @@ void RenderWidgetHostViewMac::UpdateWindowsNow() {
   [NSApp updateWindows];
 }
 
+std::pair<bool, bool>
+RenderWidgetHostViewMac::MaybeUpdateScreenInfosForHiDPI() {
+  // For HiDPI capture mode, adjust the device scale factor to
+  // increase the rendered pixel count. |new_screen_infos| always contains
+  // the unmodified original values for the display, and a copy of it is
+  // saved in |screen_infos_|, with a modification applied if applicable.
+  // When HiDPI mode is turned off (the scale override is 1.0), the original
+  // |new_screen_infos| value gets copied unchanged to |screen_infos_|.
+  display::ScreenInfos new_screen_infos = original_screen_infos_;
+  const float old_device_scale_factor =
+      new_screen_infos.current().device_scale_factor;
+  new_screen_infos.mutable_current().device_scale_factor =
+      old_device_scale_factor * scale_override_for_capture_;
+  if (screen_infos_ != new_screen_infos) {
+    DVLOG(1) << __func__ << ": Overriding device_scale_factor from "
+             << old_device_scale_factor << " to "
+             << new_screen_infos.current().device_scale_factor
+             << " for capture.";
+    const bool current_display_changed =
+        new_screen_infos.current() != screen_infos_.current();
+    screen_infos_ = new_screen_infos;
+    return {true, current_display_changed};
+  }
+  return {false, false};
+}
+
 Class GetRenderWidgetHostViewCocoaClassForTesting() {
   return [RenderWidgetHostViewCocoa class];
 }

media/base/media_switches.cc

@@ -1006,12 +1006,6 @@ const base::FeatureParam<bool>
     kHardwareSecureDecryptionFallbackOnHardwareContextReset{
         &kHardwareSecureDecryptionFallback, "on_hardware_context_reset", true};
 
-// If active, enable HiDPI mode that increases the display scale factor
-// while capturing a low-resolution tab.
-BASE_FEATURE(kWebContentsCaptureHiDpi,
-             "WebContentsCaptureHiDPI",
-             base::FEATURE_ENABLED_BY_DEFAULT);
-
 // Enables handling of hardware media keys for controlling media.
 BASE_FEATURE(kHardwareMediaKeyHandling,
              "HardwareMediaKeyHandling",

media/base/media_switches.h

@@ -377,7 +377,6 @@ MEDIA_EXPORT BASE_DECLARE_FEATURE(kCastVideoEncoderFrameDrop);
 MEDIA_EXPORT BASE_DECLARE_FEATURE(kWebCodecsVideoEncoderFrameDrop);
 MEDIA_EXPORT BASE_DECLARE_FEATURE(kWebRTCHardwareVideoEncoderFrameDrop);
 MEDIA_EXPORT BASE_DECLARE_FEATURE(kWebRTCColorAccuracy);
-MEDIA_EXPORT BASE_DECLARE_FEATURE(kWebContentsCaptureHiDpi);
 MEDIA_EXPORT BASE_DECLARE_FEATURE(kWebrtcMediaCapabilitiesParameters);
 MEDIA_EXPORT BASE_DECLARE_FEATURE(kResolutionBasedDecoderPriority);
 

testing/variations/fieldtrial_testing_config.json

@@ -24650,24 +24650,6 @@
             ]
         }
     ],
-    "WebContentsCaptureHiDPI": [
-        {
-            "platforms": [
-                "chromeos",
-                "linux",
-                "mac",
-                "windows"
-            ],
-            "experiments": [
-                {
-                    "name": "Enabled",
-                    "enable_features": [
-                        "WebContentsCaptureHiDPI"
-                    ]
-                }
-            ]
-        }
-    ],
     "WebContentsDiscard": [
         {
             "platforms": [

tools/metrics/histograms/enums.xml

@@ -15218,7 +15218,6 @@ from previous Chrome versions.
   <int value="-2072877761" label="WaylandUiScale:disabled"/>
   <int value="-2072754800" label="HelpAppAppsList:disabled"/>
   <int value="-2072471036" label="OobeHidDetectionRevamp:disabled"/>
-  <int value="-2072181147" label="WebContentsCaptureHiDPI:enabled"/>
   <int value="-2071515296" label="allow-sync-xhr-in-page-dismissal"/>
   <int value="-2071202821" label="CopyLinkToText:enabled"/>
   <int value="-2069855464"
@@ -22872,7 +22871,6 @@ from previous Chrome versions.
   <int value="982032277" label="NTPOfflineBadge:disabled"/>
   <int value="982511393" label="NTPArticleSuggestions:disabled"/>
   <int value="982805190" label="PageInfoAboutThisSiteMoreLangs:enabled"/>
-  <int value="982932009" label="WebContentsCaptureHiDPI:disabled"/>
   <int value="982983280" label="LauncherSearchControl:enabled"/>
   <int value="983084316" label="SyncUSSNigori:disabled"/>
   <int value="983236654" label="TrackingProtection3pcd:enabled"/>