Switch to double for time calculations using playback rate.

chromecast/browser/media/media_pipeline_host.cc

Index: chromecast/browser/media/media_pipeline_host.cc
diff --git a/chromecast/browser/media/media_pipeline_host.cc b/chromecast/browser/media/media_pipeline_host.cc
index ff9761205f0353fc719063dbe6b68039d55bf26e..ff3eb6926f9f567f0105f8496d637f80f457a86f 100644
--- a/chromecast/browser/media/media_pipeline_host.cc
+++ b/chromecast/browser/media/media_pipeline_host.cc
@@ -142,7 +142,7 @@ void MediaPipelineHost::Stop() {
   media_pipeline_->Stop();
 }
 
-void MediaPipelineHost::SetPlaybackRate(float playback_rate) {
+void MediaPipelineHost::SetPlaybackRate(double playback_rate) {
   DCHECK(thread_checker_.CalledOnValidThread());
   media_pipeline_->SetPlaybackRate(playback_rate);
 }