Reland "WebShare: Implement SharingServicePicker"

This is a reland of 07700ae66e

Original change's description:
> WebShare: Implement SharingServicePicker
>
> This CL completes the implementation of webshare on mac.
> The UX review is being tracked here: crbug.com/1162971
>
> To test manually:
> -launch chromium with flag 'WebShare'
> -go to https://w3c.github.io/web-share/demos/share-files.html
> -optionally, add a file to the form
> -click on Share
> -the NSSharingServicePicker should popup in the top-middle,
> overlapping the client and non-client area
>
> Bug: 1144920
> Change-Id: Ia28ad87fac82a9704c07122b57a144ce5aa5086e
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2668974
> Reviewed-by: Avi Drissman <avi@chromium.org>
> Reviewed-by: Daniel Murphy <dmurph@chromium.org>
> Reviewed-by: Eric Willigers <ericwilligers@chromium.org>
> Reviewed-by: Leonard Grey <lgrey@chromium.org>
> Reviewed-by: Dominick Ng <dominickn@chromium.org>
> Commit-Queue: Eric Willigers <ericwilligers@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#859624}

Bug: 1144920
Change-Id: Ied9df60b65fc19c366f9c0e038028563df976a5c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2737234
Reviewed-by: Avi Drissman <avi@chromium.org>
Reviewed-by: Dominick Ng <dominickn@chromium.org>
Reviewed-by: Eric Willigers <ericwilligers@chromium.org>
Reviewed-by: Leonard Grey <lgrey@chromium.org>
Reviewed-by: Daniel Murphy <dmurph@chromium.org>
Commit-Queue: Hassan Talat <hatalat@microsoft.com>
Cr-Commit-Position: refs/heads/master@{#866720}

chrome/browser/webshare/mac/sharing_service_operation.h

@@ -33,6 +33,7 @@ class SharingServiceOperation final : content::WebContentsObserver {
       const std::vector<base::FilePath>& file_paths,
       const std::string& text,
       const std::string& title,
+      const GURL& url,
       blink::mojom::ShareService::ShareCallback close_callback)>;
 
   SharingServiceOperation(const std::string& title,
@@ -59,6 +60,7 @@ class SharingServiceOperation final : content::WebContentsObserver {
       const std::vector<base::FilePath>& file_paths,
       const std::string& text,
       const std::string& title,
+      const GURL& url,
       blink::mojom::ShareService::ShareCallback close_callback);
   static SharePickerCallback& GetSharePickerCallback();
 

chrome/browser/webshare/mac/sharing_service_operation.mm

@@ -6,16 +6,20 @@
 
 #include <AppKit/AppKit.h>
 
+#include <utility>
+
 #include "base/bind.h"
 #include "base/guid.h"
 #include "base/i18n/file_util_icu.h"
 #include "base/mac/scoped_nsobject.h"
+#include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/webshare/prepare_directory_task.h"
 #include "chrome/browser/webshare/prepare_subdirectory_task.h"
 #include "chrome/browser/webshare/share_service_impl.h"
 #include "chrome/browser/webshare/store_files_task.h"
 #include "content/public/browser/browser_context.h"
+#include "content/public/browser/render_widget_host_view.h"
 #include "content/public/browser/storage_partition.h"
 #include "content/public/browser/web_contents.h"
 #include "net/base/filename_util.h"
@@ -60,7 +64,7 @@ void SharingServiceOperation::Share(
 
   if (shared_files_.size() == 0) {
     GetSharePickerCallback().Run(
-        web_contents(), file_paths_, text_, title_,
+        web_contents(), file_paths_, text_, title_, url_,
         base::BindOnce(&SharingServiceOperation::OnShowSharePicker,
                        weak_factory_.GetWeakPtr()));
     return;
@@ -94,6 +98,8 @@ void SharingServiceOperation::OnPrepareDirectory(
 
   for (const auto& file : shared_files_) {
     std::string file_name = file->name;
+    // Protecting against including paths in a file name.
+    base::ReplaceSubstringsAfterOffset(&file_name, 0, "/", "_");
     base::i18n::ReplaceIllegalCharactersInPath(&file_name, '_');
     file_paths_.push_back(
         GenerateUniqueSubDirectory(directory_).Append(file_name));
@@ -125,18 +131,24 @@ void SharingServiceOperation::OnPrepareSubDirectory(
 
 void SharingServiceOperation::OnStoreFiles(blink::mojom::ShareError error) {
   if (!web_contents() || error != blink::mojom::ShareError::OK) {
+    PrepareDirectoryTask::ScheduleSharedFileDeletion(
+        std::move(file_paths_), base::TimeDelta::FromMinutes(0));
     std::move(callback_).Run(error);
     return;
   }
 
   GetSharePickerCallback().Run(
-      web_contents(), file_paths_, text_, title_,
+      web_contents(), file_paths_, text_, title_, url_,
       base::BindOnce(&SharingServiceOperation::OnShowSharePicker,
                      weak_factory_.GetWeakPtr()));
 }
 
 void SharingServiceOperation::OnShowSharePicker(
     blink::mojom::ShareError error) {
+  if (file_paths_.size() > 0) {
+    PrepareDirectoryTask::ScheduleSharedFileDeletion(
+        std::move(file_paths_), base::TimeDelta::FromMinutes(0));
+  }
   std::move(callback_).Run(error);
 }
 
@@ -146,15 +158,15 @@ void SharingServiceOperation::ShowSharePicker(
     const std::vector<base::FilePath>& file_paths,
     const std::string& text,
     const std::string& title,
+    const GURL& url,
     blink::mojom::ShareService::ShareCallback callback) {
   std::vector<std::string> file_paths_as_utf8;
   for (const auto& file_path : file_paths) {
     file_paths_as_utf8.emplace_back(file_path.AsUTF8Unsafe());
   }
 
-  // TODO(crbug.com/1144920): Add & invoke NSSharingServicePicker in
-  // remote_cocoa
-  std::move(callback).Run(blink::mojom::ShareError::INTERNAL_ERROR);
+  web_contents->GetRenderWidgetHostView()->ShowSharePicker(
+      title, text, url.spec(), file_paths_as_utf8, std::move(callback));
 }
 
 // static

chrome/browser/webshare/mac/sharing_service_operation_browsertest.cc

@@ -0,0 +1,61 @@
+// Copyright 2021 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/webshare/mac/sharing_service_operation.h"
+
+#include "base/test/bind.h"
+#include "base/test/scoped_feature_list.h"
+#include "chrome/browser/ui/browser.h"
+#include "chrome/browser/ui/tabs/tab_strip_model.h"
+#include "chrome/common/chrome_features.h"
+#include "chrome/test/base/in_process_browser_test.h"
+#include "chrome/test/base/ui_test_utils.h"
+#include "content/public/test/browser_test.h"
+#include "content/public/test/browser_test_utils.h"
+#include "net/test/embedded_test_server/embedded_test_server.h"
+#include "third_party/blink/public/mojom/webshare/webshare.mojom.h"
+#include "url/gurl.h"
+
+namespace webshare {
+
+class SharingServiceOperationBrowserTest : public InProcessBrowserTest {
+ public:
+  SharingServiceOperationBrowserTest() {
+    feature_list_.InitAndEnableFeature(features::kWebShare);
+  }
+
+  GURL GetAppUrl() const {
+    return embedded_test_server()->GetURL("/webshare/index.html");
+  }
+
+ private:
+  base::test::ScopedFeatureList feature_list_;
+};
+
+IN_PROC_BROWSER_TEST_F(SharingServiceOperationBrowserTest,
+                       ShareIllegalFilename) {
+  const std::string script =
+      "share_multiple_custom_files_url('../sample.csv', '..sample.csv')";
+  ASSERT_TRUE(embedded_test_server()->Start());
+  ui_test_utils::NavigateToURL(browser(), GetAppUrl());
+  content::WebContents* const contents =
+      browser()->tab_strip_model()->GetActiveWebContents();
+  std::vector<base::FilePath> file_paths;
+
+  ui_test_utils::NavigateToURL(browser(), GetAppUrl());
+  SharingServiceOperation::SetSharePickerCallbackForTesting(
+      base::BindLambdaForTesting(
+          [](content::WebContents* in_contents,
+             const std::vector<base::FilePath>& file_paths,
+             const std::string& text, const std::string& title, const GURL& url,
+             blink::mojom::ShareService::ShareCallback close_callback) {
+            EXPECT_EQ(file_paths[0].BaseName().value(), "_._sample.csv");
+            EXPECT_EQ(file_paths[1].BaseName().value(), "_.sample.csv");
+            std::move(close_callback).Run(blink::mojom::ShareError::OK);
+          }));
+
+  EXPECT_EQ("share succeeded", content::EvalJs(contents, script));
+}
+
+}  // namespace webshare

chrome/browser/webshare/share_service_browsertest.cc

@@ -67,6 +67,7 @@ class ShareServiceBrowserTest : public InProcessBrowserTest {
       const std::vector<base::FilePath>& file_paths,
       const std::string& text,
       const std::string& title,
+      const GURL& url,
       blink::mojom::ShareService::ShareCallback close_callback) {
     std::move(close_callback).Run(blink::mojom::ShareError::OK);
   }

chrome/browser/webshare/share_service_unittest.cc

@@ -155,6 +155,7 @@ class ShareServiceUnitTest : public ChromeRenderViewHostTestHarness {
       const std::vector<base::FilePath>& file_paths,
       const std::string& text,
       const std::string& title,
+      const GURL& url,
       blink::mojom::ShareService::ShareCallback close_callback) {
     std::move(close_callback).Run(blink::mojom::ShareError::OK);
   }

chrome/test/BUILD.gn

@@ -1861,6 +1861,11 @@ if (!is_android) {
       sources += [ "../browser/webshare/share_service_browsertest.cc" ]
     }
 
+    if (is_mac) {
+      sources +=
+          [ "../browser/webshare/mac/sharing_service_operation_browsertest.cc" ]
+    }
+
     if (enable_dice_support) {
       sources += [
         "../browser/policy/cloud/user_policy_signin_service_browsertest.cc",

chrome/test/data/webshare/index.html

@@ -142,6 +142,19 @@
         return ('share failed: ' + error);
       }
     }
+
+    async function share_multiple_custom_files_url(first_filename, second_filename) {
+      try {
+        const first_file = create_file(first_filename, 'text/csv', 12);
+        const second_file = create_file(second_filename, 'text/csv', 15);
+        await navigator.share({files: [first_file, second_file],
+                               url: "https://example.com/"});
+        return 'share succeeded';
+      } catch(error) {
+        return ('share failed: ' + error);
+      }
+    }
+
   </script>
 </head>
 <body>

content/app_shim_remote_cocoa/DEPS

@@ -31,4 +31,5 @@ include_rules = [
   "+content/public/common/content_features.h",
   "+content/public/common/drop_data.h",
   "+content/public/common/widget_type.h",
+  "+third_party/blink/public/mojom/webshare/webshare.mojom.h",
 ]

content/app_shim_remote_cocoa/render_widget_host_ns_view_bridge.h

@@ -10,6 +10,7 @@
 #import "base/mac/scoped_nsobject.h"
 #import "content/app_shim_remote_cocoa/popup_window_mac.h"
 #import "content/app_shim_remote_cocoa/render_widget_host_view_cocoa.h"
+#include "content/app_shim_remote_cocoa/sharing_service_picker.h"
 #include "content/common/render_widget_host_ns_view.mojom.h"
 #include "content/public/common/widget_type.h"
 #include "mojo/public/cpp/bindings/associated_receiver.h"
@@ -68,6 +69,12 @@ class RenderWidgetHostNSViewBridge : public mojom::RenderWidgetHostNSView,
   void LockKeyboard(
       const base::Optional<std::vector<uint32_t>>& uint_dom_codes) override;
   void UnlockKeyboard() override;
+  void ShowSharingServicePicker(
+      const std::string& title,
+      const std::string& text,
+      const std::string& url,
+      const std::vector<std::string>& file_paths,
+      ShowSharingServicePickerCallback callback) override;
 
  private:
   bool IsPopup() const { return !!popup_window_; }

content/app_shim_remote_cocoa/render_widget_host_ns_view_bridge.mm

@@ -271,4 +271,14 @@ void RenderWidgetHostNSViewBridge::UnlockKeyboard() {
   [cocoa_view_ unlockKeyboard];
 }
 
+void RenderWidgetHostNSViewBridge::ShowSharingServicePicker(
+    const std::string& title,
+    const std::string& text,
+    const std::string& url,
+    const std::vector<std::string>& file_paths,
+    ShowSharingServicePickerCallback callback) {
+  ShowSharingServicePickerForView(cocoa_view_, title, text, url, file_paths,
+                                  std::move(callback));
+}
+
 }  // namespace remote_cocoa

content/app_shim_remote_cocoa/sharing_service_picker.h

@@ -0,0 +1,26 @@
+// Copyright 2021 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CONTENT_APP_SHIM_REMOTE_COCOA_SHARING_SERVICE_PICKER_H_
+#define CONTENT_APP_SHIM_REMOTE_COCOA_SHARING_SERVICE_PICKER_H_
+
+#include <string>
+
+#include <AppKit/AppKit.h>
+
+#include "content/common/render_widget_host_ns_view.mojom.h"
+
+namespace remote_cocoa {
+
+void ShowSharingServicePickerForView(
+    NSView* owning_view,
+    const std::string& title,
+    const std::string& text,
+    const std::string& url,
+    const std::vector<std::string>& file_paths,
+    mojom::RenderWidgetHostNSView::ShowSharingServicePickerCallback callback);
+
+}  // namespace remote_cocoa
+
+#endif  // CONTENT_APP_SHIM_REMOTE_COCOA_SHARING_SERVICE_PICKER_H_

content/app_shim_remote_cocoa/sharing_service_picker.mm

@@ -0,0 +1,114 @@
+// Copyright 2021 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "content/app_shim_remote_cocoa/sharing_service_picker.h"
+
+#include <utility>
+
+#include "base/mac/scoped_nsobject.h"
+#include "base/strings/sys_string_conversions.h"
+#include "third_party/blink/public/mojom/webshare/webshare.mojom.h"
+#include "url/gurl.h"
+
+@interface SharingServicePicker
+    : NSObject <NSSharingServiceDelegate, NSSharingServicePickerDelegate>
+// Displays the NSSharingServicePicker which is positioned center and overlaps
+// WebContents and the Non Client area.
+- (void)show;
+@end
+
+@implementation SharingServicePicker {
+  base::scoped_nsobject<NSSharingServicePicker> picker_;
+  remote_cocoa::mojom::RenderWidgetHostNSView::ShowSharingServicePickerCallback
+      callback_;
+  NSView* view_;
+}
+
+- (instancetype)initWithItems:(NSArray*)items
+                     callback:(remote_cocoa::mojom::RenderWidgetHostNSView::
+                                   ShowSharingServicePickerCallback)cb
+                         view:(NSView*)view {
+  if ((self = [super init])) {
+    picker_.reset([[NSSharingServicePicker alloc] initWithItems:items]);
+    picker_.get().delegate = self;
+    callback_ = std::move(cb);
+    view_ = view;
+  }
+  return self;
+}
+
+- (void)sharingServicePicker:(NSSharingServicePicker*)sharingServicePicker
+     didChooseSharingService:(NSSharingService*)service {
+  // When the NSSharingServicePicker gets invoked but then the picker gets
+  // dismissed, this is the only delegate method called, and it's called with a
+  // nil service, so run the callback.
+  if (!service) {
+    std::move(callback_).Run(blink::mojom::ShareError::CANCELED);
+  }
+}
+
+- (void)show {
+  NSRect viewFrame = [view_ frame];
+  CGSize size = viewFrame.size;
+  NSRect rect = NSMakeRect(size.width / 2, size.height, 1, 1);
+  [picker_ showRelativeToRect:rect ofView:view_ preferredEdge:NSMaxXEdge];
+}
+
+- (void)sharingService:(NSSharingService*)sharingService
+         didShareItems:(NSArray*)items {
+  std::move(callback_).Run(blink::mojom::ShareError::OK);
+}
+
+- (void)sharingService:(NSSharingService*)sharingService
+    didFailToShareItems:(NSArray*)items
+                  error:(NSError*)error {
+  error.code == NSUserCancelledError
+      ? std::move(callback_).Run(blink::mojom::ShareError::CANCELED)
+      : std::move(callback_).Run(blink::mojom::ShareError::INTERNAL_ERROR);
+}
+
+- (id<NSSharingServiceDelegate>)
+         sharingServicePicker:(NSSharingServicePicker*)sharingServicePicker
+    delegateForSharingService:(NSSharingService*)sharingService {
+  return self;
+}
+
+- (NSWindow*)sharingService:(NSSharingService*)sharingService
+    sourceWindowForShareItems:(NSArray*)items
+          sharingContentScope:(NSSharingContentScope*)sharingContentScope {
+  return [view_ window];
+}
+
+@end
+
+namespace remote_cocoa {
+
+void ShowSharingServicePickerForView(
+    NSView* view,
+    const std::string& title,
+    const std::string& text,
+    const std::string& url,
+    const std::vector<std::string>& file_paths,
+    mojom::RenderWidgetHostNSView::ShowSharingServicePickerCallback callback) {
+  NSString* ns_title = base::SysUTF8ToNSString(title);
+  NSString* ns_url = base::SysUTF8ToNSString(url);
+  NSString* ns_text = base::SysUTF8ToNSString(text);
+
+  NSMutableArray* items =
+      [NSMutableArray arrayWithArray:@[ ns_title, ns_url, ns_text ]];
+
+  for (const auto& file_path : file_paths) {
+    NSString* ns_file_path = base::SysUTF8ToNSString(file_path);
+    NSURL* file_url = [NSURL fileURLWithPath:ns_file_path];
+    [items addObject:file_url];
+  }
+
+  base::scoped_nsobject<SharingServicePicker> picker(
+      [[SharingServicePicker alloc] initWithItems:items
+                                         callback:std::move(callback)
+                                             view:view]);
+  [picker.get() show];
+}
+
+}  // namespace remote_cocoa

content/browser/BUILD.gn

@@ -2742,6 +2742,8 @@ source_set("browser") {
       "../app_shim_remote_cocoa/render_widget_host_ns_view_host_helper.h",
       "../app_shim_remote_cocoa/render_widget_host_view_cocoa.h",
       "../app_shim_remote_cocoa/render_widget_host_view_cocoa.mm",
+      "../app_shim_remote_cocoa/sharing_service_picker.h",
+      "../app_shim_remote_cocoa/sharing_service_picker.mm",
       "../app_shim_remote_cocoa/web_contents_view_cocoa.h",
       "../app_shim_remote_cocoa/web_contents_view_cocoa.mm",
     ]

content/browser/renderer_host/render_widget_host_view_child_frame.cc

@@ -755,6 +755,13 @@ void RenderWidgetHostViewChildFrame::SpeakSelection() {}
 
 void RenderWidgetHostViewChildFrame::SetWindowFrameInScreen(
     const gfx::Rect& rect) {}
+
+void RenderWidgetHostViewChildFrame::ShowSharePicker(
+    const std::string& title,
+    const std::string& text,
+    const std::string& url,
+    const std::vector<std::string>& file_paths,
+    blink::mojom::ShareService::ShareCallback callback) {}
 #endif  // defined(OS_MAC)
 
 void RenderWidgetHostViewChildFrame::CopyFromSurface(

content/browser/renderer_host/render_widget_host_view_child_frame.h

@@ -35,6 +35,10 @@
 #include "ui/gfx/geometry/rect.h"
 #include "ui/gfx/native_widget_types.h"
 
+#if defined(OS_MAC)
+#include "third_party/blink/public/mojom/webshare/webshare.mojom.h"
+#endif  // defined(OS_MAC)
+
 namespace content {
 class CrossProcessFrameConnector;
 class RenderWidgetHost;
@@ -147,6 +151,12 @@ class CONTENT_EXPORT RenderWidgetHostViewChildFrame
   void ShowDefinitionForSelection() override;
   void SpeakSelection() override;
   void SetWindowFrameInScreen(const gfx::Rect& rect) override;
+  void ShowSharePicker(
+      const std::string& title,
+      const std::string& text,
+      const std::string& url,
+      const std::vector<std::string>& file_paths,
+      blink::mojom::ShareService::ShareCallback callback) override;
 #endif  // defined(OS_MAC)
 
   blink::mojom::InputEventResultState FilterInputEvent(

content/browser/renderer_host/render_widget_host_view_mac.h

@@ -24,6 +24,7 @@
 #include "content/common/render_widget_host_ns_view.mojom.h"
 #include "mojo/public/cpp/bindings/associated_receiver.h"
 #include "mojo/public/cpp/bindings/associated_remote.h"
+#include "third_party/blink/public/mojom/webshare/webshare.mojom.h"
 #include "ui/accelerated_widget_mac/accelerated_widget_mac.h"
 #include "ui/base/cocoa/accessibility_focus_overrider.h"
 #include "ui/base/cocoa/remote_layer_api.h"
@@ -479,6 +480,13 @@ class CONTENT_EXPORT RenderWidgetHostViewMac
 
   MouseWheelPhaseHandler* GetMouseWheelPhaseHandler() override;
 
+  void ShowSharePicker(
+      const std::string& title,
+      const std::string& text,
+      const std::string& url,
+      const std::vector<std::string>& file_paths,
+      blink::mojom::ShareService::ShareCallback callback) override;
+
  protected:
   // This class is to be deleted through the Destroy method.
   ~RenderWidgetHostViewMac() override;

content/browser/renderer_host/render_widget_host_view_mac.mm

@@ -1412,6 +1412,16 @@ MouseWheelPhaseHandler* RenderWidgetHostViewMac::GetMouseWheelPhaseHandler() {
   return &mouse_wheel_phase_handler_;
 }
 
+void RenderWidgetHostViewMac::ShowSharePicker(
+    const std::string& title,
+    const std::string& text,
+    const std::string& url,
+    const std::vector<std::string>& file_paths,
+    blink::mojom::ShareService::ShareCallback callback) {
+  ns_view_->ShowSharingServicePicker(title, text, url, file_paths,
+                                     std::move(callback));
+}
+
 ///////////////////////////////////////////////////////////////////////////////
 // RenderWidgetHostNSViewHostHelper and mojom::RenderWidgetHostNSViewHost
 // implementation:

content/common/render_widget_host_ns_view.mojom

@@ -6,6 +6,7 @@ module remote_cocoa.mojom;
 
 import "mojo/public/mojom/base/string16.mojom";
 import "third_party/blink/public/mojom/input/input_handler.mojom";
+import "third_party/blink/public/mojom/webshare/share_error.mojom";
 import "ui/base/mojom/attributed_string.mojom";
 import "ui/base/cursor/mojom/cursor.mojom";
 import "ui/base/ime/mojom/ime_types.mojom";
@@ -92,6 +93,14 @@ interface RenderWidgetHostNSView {
 
   // Stop intercepting keyboard events.
   UnlockKeyboard();
+
+  // Show the NSSharingServicePicker using the requested data that is passed and
+  // returning the result of that action.
+  ShowSharingServicePicker(string title,
+                           string text,
+                           string url,
+                           array<string> file_paths)
+    => (blink.mojom.ShareError error);
 };
 
 // The interface through which the RenderWidgetHostViewCocoa NSView in the app

content/public/browser/render_widget_host_view.h

@@ -22,6 +22,10 @@
 #include "ui/gfx/native_widget_types.h"
 #include "ui/gfx/range/range.h"
 
+#if defined(OS_MAC)
+#include "third_party/blink/public/mojom/webshare/webshare.mojom.h"
+#endif
+
 namespace gfx {
 class Insets;
 class Point;
@@ -258,6 +262,23 @@ class CONTENT_EXPORT RenderWidgetHostView {
   // Allows to update the widget's screen rects when it is not attached to
   // a window (e.g. in headless mode).
   virtual void SetWindowFrameInScreen(const gfx::Rect& rect) = 0;
+
+  // Invoked by browser implementation of the navigator.share() to trigger the
+  // NSSharingServicePicker.
+  //
+  // |title|, |text|, |url| makes up the requested data that is passed to the
+  // picker after being converted to NSString.
+  // |file_paths| is the set of paths to files to be shared passed onto the
+  // picker after being converted to NSURL.
+  // |callback| returns the result from the NSSharingServicePicker depending
+  // upon the user's action.
+  virtual void ShowSharePicker(
+      const std::string& title,
+      const std::string& text,
+      const std::string& url,
+      const std::vector<std::string>& file_paths,
+      blink::mojom::ShareService::ShareCallback callback) = 0;
+
 #endif  // defined(OS_MAC)
 
   // Indicates that this view should show the contents of |view| if it doesn't

content/test/test_render_view_host.cc

@@ -160,6 +160,13 @@ void TestRenderWidgetHostView::SpeakSelection() {
 }
 
 void TestRenderWidgetHostView::SetWindowFrameInScreen(const gfx::Rect& rect) {}
+
+void TestRenderWidgetHostView::ShowSharePicker(
+    const std::string& title,
+    const std::string& text,
+    const std::string& url,
+    const std::vector<std::string>& file_paths,
+    blink::mojom::ShareService::ShareCallback callback) {}
 #endif
 
 gfx::Rect TestRenderWidgetHostView::GetBoundsInRootWindow() {

content/test/test_render_view_host.h

@@ -30,6 +30,10 @@
 #include "ui/aura/window.h"
 #endif
 
+#if defined(OS_MAC)
+#include "third_party/blink/public/mojom/webshare/webshare.mojom.h"
+#endif
+
 // This file provides a testing framework for mocking out the RenderProcessHost
 // layer. It allows you to test RenderViewHost, WebContentsImpl,
 // NavigationController, and other layers above that without running an actual
@@ -77,6 +81,12 @@ class TestRenderWidgetHostView : public RenderWidgetHostViewBase,
   void ShowDefinitionForSelection() override {}
   void SpeakSelection() override;
   void SetWindowFrameInScreen(const gfx::Rect& rect) override;
+  void ShowSharePicker(
+      const std::string& title,
+      const std::string& text,
+      const std::string& url,
+      const std::vector<std::string>& file_paths,
+      blink::mojom::ShareService::ShareCallback callback) override;
 #endif  // defined(OS_MAC)
 
   // Advances the fallback surface to the first surface after navigation. This