Implement Chrome Extension TabCapture API.

content/browser/renderer_host/media/media_stream_manager.cc

Index: content/browser/renderer_host/media/media_stream_manager.cc
diff --git a/content/browser/renderer_host/media/media_stream_manager.cc b/content/browser/renderer_host/media/media_stream_manager.cc
index 6bf60c920a2ed2824fddd5f36d546d9b4c550124..4af796f44ad7a4be83d3b8f2cfb27643b04f3a93 100644
--- a/content/browser/renderer_host/media/media_stream_manager.cc
+++ b/content/browser/renderer_host/media/media_stream_manager.cc
@@ -7,6 +7,7 @@
 #include <list>
 
 #include "base/bind.h"
+#include "base/command_line.h"
 #include "base/compiler_specific.h"
 #include "base/logging.h"
 #include "base/rand_util.h"
@@ -19,6 +20,7 @@
 #include "content/public/browser/content_browser_client.h"
 #include "content/public/browser/media_observer.h"
 #include "content/public/browser/media_request_state.h"
+#include "content/public/common/content_switches.h"
 #include "googleurl/src/gurl.h"
 
 #if defined(OS_WIN)
@@ -244,7 +246,9 @@ void MediaStreamManager::GenerateStreamForDevice(
                                               options,
                                               security_origin);
 
-  if (!security_origin.SchemeIs(kExtensionScheme) ||
+  if (!CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kEnableTabCapture) ||
+      !security_origin.SchemeIs(kExtensionScheme) ||
       (options.audio_type != content::MEDIA_TAB_AUDIO_CAPTURE &&
        options.audio_type != content::MEDIA_NO_SERVICE) ||
       (options.video_type != content::MEDIA_TAB_VIDEO_CAPTURE &&