[chromecast] Fix build with enable_mojo_media=true.

chromecast/browser/cast_content_browser_client.cc

Index: chromecast/browser/cast_content_browser_client.cc
diff --git a/chromecast/browser/cast_content_browser_client.cc b/chromecast/browser/cast_content_browser_client.cc
index 00cf5d43076e80831b514fdf9f513f514ca15b37..dc5902ac7e67d80b42745ebef9874ac48bb4bbe7 100644
--- a/chromecast/browser/cast_content_browser_client.cc
+++ b/chromecast/browser/cast_content_browser_client.cc
@@ -71,7 +71,8 @@ static scoped_ptr<mojo::ShellClient> CreateCastMojoMediaApplication(
     CastContentBrowserClient* browser_client) {
   scoped_ptr<::media::MojoMediaClient> mojo_media_client(
       new media::CastMojoMediaClient(
-          browser_client->GetCmaMediaPipelineClient()));
+          base::Bind(&CastContentBrowserClient::CreateMediaPipelineBackend,
+                     base::Unretained(browser_client))));
   return scoped_ptr<mojo::ShellClient>(
       new ::media::MojoMediaApplication(std::move(mojo_media_client)));
 }