Chromecast: fix SwitchingMediaRenderer::Initialize signature

BUG=none

Review URL: https://codereview.chromium.org/975973003

Cr-Commit-Position: refs/heads/master@{#319006}

chromecast/media/base/switching_media_renderer.cc

@@ -26,7 +26,7 @@ SwitchingMediaRenderer::~SwitchingMediaRenderer() {
 
 void SwitchingMediaRenderer::Initialize(
     ::media::DemuxerStreamProvider* demuxer_stream_provider,
-    const base::Closure& init_cb,
+    const ::media::PipelineStatusCB& init_cb,
     const ::media::StatisticsCB& statistics_cb,
     const ::media::BufferingStateCB& buffering_state_cb,
     const ::media::Renderer::PaintCB& paint_cb,

chromecast/media/base/switching_media_renderer.h

@@ -33,7 +33,7 @@ class SwitchingMediaRenderer : public ::media::Renderer {
   // ::media::Renderer implementation:
   void Initialize(
       ::media::DemuxerStreamProvider* demuxer_stream_provider,
-      const base::Closure& init_cb,
+      const ::media::PipelineStatusCB& init_cb,
       const ::media::StatisticsCB& statistics_cb,
       const ::media::BufferingStateCB& buffering_state_cb,
       const ::media::Renderer::PaintCB& paint_cb,