Media Remoting: Draw remoting interstitial on poster image.

content/renderer/image_downloader/image_downloader_impl.cc

Index: content/renderer/image_downloader/image_downloader_impl.cc
diff --git a/content/renderer/image_downloader/image_downloader_impl.cc b/content/renderer/image_downloader/image_downloader_impl.cc
index a7679900966e61f80eedefda12fd1f9fe4c42cdd..71115669d539dbd449bb6e2f3d744fea2492ab1e 100644
--- a/content/renderer/image_downloader/image_downloader_impl.cc
+++ b/content/renderer/image_downloader/image_downloader_impl.cc
@@ -132,6 +132,12 @@ ImageDownloaderImpl::ImageDownloaderImpl(
       base::Bind(&ImageDownloaderImpl::OnDestruct, base::Unretained(this)));
 }
 
+ImageDownloaderImpl::ImageDownloaderImpl(RenderFrame* render_frame)
+    : RenderFrameObserver(render_frame), binding_(this) {
+  DCHECK(render_frame);
+  RenderThread::Get()->AddObserver(this);
+}
+
 ImageDownloaderImpl::~ImageDownloaderImpl() {
   RenderThread* thread = RenderThread::Get();
   // As ImageDownloaderImpl is a strong binding with message pipe, the