Desktop chrome tab capture-chooseDesktopMedia()

chrome/browser/media/desktop_media_list.h

 // Copyright 2013 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 CHROME_BROWSER_MEDIA_DESKTOP_MEDIA_LIST_H_
 #define CHROME_BROWSER_MEDIA_DESKTOP_MEDIA_LIST_H_
 
-#include "base/strings/string16.h"
 #include "base/time/time.h"
 #include "content/public/browser/desktop_media_id.h"
+#include "content/public/browser/web_contents_observer.h"
+#include "ui/gfx/image/image.h"
 #include "ui/gfx/image/image_skia.h"
 
 class DesktopMediaListObserver;
 
 // DesktopMediaList provides the list of desktop media source (screens, windows,
 // tabs), and their thumbnails, to the desktop media picker dialog. It
 // transparently updates the list in the background, and notifies the desktop
 // media picker when something changes.
 class DesktopMediaList {
  public:
@@ skipping 29 matching lines @@
   // notifications will be generated for each existing source as it is
   // enumerated. After the initial enumeration the model will be refreshed based
   // on the update period, and notifications generated only for changes in the
   // model.
   virtual void StartUpdating(DesktopMediaListObserver* observer) = 0;
 
   virtual int GetSourceCount() const = 0;
   virtual const Source& GetSource(int index) const = 0;
 };
 
+// Create a image with an enlarged favicon on its center and black boundary.
+// If fails, an empty image will return.
+// The function is used to create a thumbnail for chrome tab preview.
+gfx::ImageSkia CreateEnlargedFaviconImage(gfx::Size size, gfx::Image& favicon);
+
+// Observer of WebContents to detect whether WebContents has been destroyed.
+class MediaListWebContentsObserver : public content::WebContentsObserver {

[Avi (use Gerrit), 2016/01/08 17:11:38]

This is not a useful class; it exists but overrides nothing. You use the
automatic nulling out of the pointer, but I've never seen that done before. Its
use doesn't make sense either; I'm commenting there.

You should remove it.

[GeorgeZ, 2016/01/08 19:39:02]

Done.

+ public:
+  explicit MediaListWebContentsObserver(content::WebContents* contents) {
+    Observe(contents);
+  }
+
+  DISALLOW_COPY_AND_ASSIGN(MediaListWebContentsObserver);
+};
+
 #endif  // CHROME_BROWSER_MEDIA_DESKTOP_MEDIA_LIST_H_