Extend content::DesktopMediaID to allow Aura windows as capture sources.

content/browser/renderer_host/media/desktop_capture_device_aura_unittest.cc

Index: content/browser/renderer_host/media/desktop_capture_device_aura_unittest.cc
diff --git a/content/browser/renderer_host/media/desktop_capture_device_aura_unittest.cc b/content/browser/renderer_host/media/desktop_capture_device_aura_unittest.cc
index 1e87c69300532987a940c61bcaf6415d3b751287..182715a5c1a7126ad659445af2741ab619d03d1d 100644
--- a/content/browser/renderer_host/media/desktop_capture_device_aura_unittest.cc
+++ b/content/browser/renderer_host/media/desktop_capture_device_aura_unittest.cc
@@ -6,6 +6,7 @@
 
 #include "base/synchronization/waitable_event.h"
 #include "content/browser/browser_thread_impl.h"
+#include "content/public/browser/desktop_media_id.h"
 #include "media/video/capture/video_capture_types.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ -94,9 +95,9 @@ class DesktopCaptureDeviceAuraTest : public testing::Test {
 };
 
 TEST_F(DesktopCaptureDeviceAuraTest, StartAndStop) {
-  DesktopMediaID source(DesktopMediaID::TYPE_SCREEN, 0);
   scoped_ptr<media::VideoCaptureDevice> capture_device(
-      DesktopCaptureDeviceAura::Create(source));
+      DesktopCaptureDeviceAura::Create(
+          content::DesktopMediaID::RegisterAuraWindow(root_window())));
 
   scoped_ptr<MockDeviceClient> client(new MockDeviceClient());
   EXPECT_CALL(*client, OnError()).Times(0);