Add CombinedDesktopMediaList class

chrome/browser/media/desktop_media_list_base.h

 // Copyright 2016 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_BASE_H_
 #define CHROME_BROWSER_MEDIA_DESKTOP_MEDIA_LIST_BASE_H_
 
 #include "chrome/browser/media/desktop_media_list.h"
 #include "content/public/browser/desktop_media_id.h"
 
 // Thumbnail size is 100*100 pixels
 static const int kDefaultThumbnailSize = 100;
 
-// Base class for DesktopMedaiList implementations. Implements logic shared
+// Base class for DesktopMediaList implementations. Implements logic shared
 // between implementations. Specifically it's responsible for keeping current
 // list of sources and calling the observer when the list changes.
 class DesktopMediaListBase : public DesktopMediaList {
  public:
+  struct SourceDescription {

[Sergey Ulanov, 2016/01/27 00:36:31]

Why does it need to be public.

[GeorgeZ, 2016/01/27 22:57:16]

Good catch. This struct was used in unit test TabDesktopMediaListTest. I move it
back to protected.

+    SourceDescription(content::DesktopMediaID id, const base::string16& name);
+
+    content::DesktopMediaID id;
+    base::string16 name;
+  };
+
   explicit DesktopMediaListBase(base::TimeDelta update_period);
   ~DesktopMediaListBase() override;
 
   // DesktopMediaList interface.
   void SetUpdatePeriod(base::TimeDelta period) override;
   void SetThumbnailSize(const gfx::Size& thumbnail_size) override;
   void SetViewDialogWindowId(content::DesktopMediaID dialog_id) override;
   void StartUpdating(DesktopMediaListObserver* observer) override;
   int GetSourceCount() const override;
   const Source& GetSource(int index) const override;
 
  protected:
-  struct SourceDescription {
-    SourceDescription(content::DesktopMediaID id, const base::string16& name);
-
-    content::DesktopMediaID id;
-    base::string16 name;
-  };
-
   virtual void Refresh() = 0;
 
   // Update source media list to observer.
   void UpdateSourcesList(const std::vector<SourceDescription>& new_sources);
 
   // Update a thumbnail to observer.
   void UpdateSourceThumbnail(content::DesktopMediaID id,
                              const gfx::ImageSkia& image);
 
   // Post a task for next list update.
@@ skipping 16 matching lines @@
 
   // The observer passed to StartUpdating().
   DesktopMediaListObserver* observer_ = nullptr;
 
   base::WeakPtrFactory<DesktopMediaListBase> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(DesktopMediaListBase);
 };
 
 #endif  // CHROME_BROWSER_MEDIA_DESKTOP_MEDIA_LIST_BASE_H_