Desktop chrome tab capture-chooseDesktopMedia()

chrome/browser/media/desktop_media_list.h

Index: chrome/browser/media/desktop_media_list.h
diff --git a/chrome/browser/media/desktop_media_list.h b/chrome/browser/media/desktop_media_list.h
index 86ac37c02f869e0c1f2813b84ac5bbbbac0c38f6..77a113c6d2cbda8d0f3aef5869515121661166e5 100644
--- a/chrome/browser/media/desktop_media_list.h
+++ b/chrome/browser/media/desktop_media_list.h
@@ -5,9 +5,14 @@
 #ifndef CHROME_BROWSER_MEDIA_DESKTOP_MEDIA_LIST_H_
 #define CHROME_BROWSER_MEDIA_DESKTOP_MEDIA_LIST_H_
 
+#include "base/id_map.h"
+#include "base/memory/singleton.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.h"
+#include "content/public/browser/web_contents_observer.h"
+#include "ui/gfx/image/image.h"
 #include "ui/gfx/image/image_skia.h"
 
 class DesktopMediaListObserver;
@@ -57,4 +62,33 @@ class DesktopMediaList {
   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);
+
+// Register WebContents.
+class WebContentsRegistry : public content::WebContentsObserver {
+ public:
+  static WebContentsRegistry* GetInstance();
+
+  // Return an id to represent the WebContents.
+  int RegisterWebContents(content::WebContents* web_contents);
+  // Get a registed WebContents by id. If the Webcontent is destroyed, a nullptr
+  // will be return.
+  content::WebContents* GetWebContentsById(int id);
+
+ private:
+  friend struct base::DefaultSingletonTraits<WebContentsRegistry>;
+  WebContentsRegistry();
+  ~WebContentsRegistry() override;
+
+  // content::WebContentsObserver overrides.
+  void WebContentsDestroyed(content::WebContents* web_contents) override;
+
+  IDMap<content::WebContents> registered_web_contents_;
+
+  DISALLOW_COPY_AND_ASSIGN(WebContentsRegistry);
+};
+
 #endif  // CHROME_BROWSER_MEDIA_DESKTOP_MEDIA_LIST_H_