Rewrite media::Pipeline state transition machinery and simplify shutdown.

media/base/media_log.cc

Index: media/base/media_log.cc
diff --git a/media/base/media_log.cc b/media/base/media_log.cc
index e47286d002212e846e2cf432faa1192c2bc5ce1e..a44883b204de91840ff52293c9e2f70a2549bd76 100644
--- a/media/base/media_log.cc
+++ b/media/base/media_log.cc
@@ -71,12 +71,10 @@ const char* MediaLog::PipelineStateToString(Pipeline::State state) {
       return "initAudioRenderer";
     case Pipeline::kInitVideoRenderer:
       return "initVideoRenderer";
-    case Pipeline::kPausing:
-      return "pausing";
+    case Pipeline::kInitPrerolling:

[acolwell GONE FROM CHROMIUM, 2012/09/06 09:19:10]

Any reason to not reuse Pipeline::GetStateString() here?

[scherkus (not reviewing), 2012/09/06 15:33:20]

!!!!!!!!!

I can't believe I never thought of this before!

+      return "initPrerolling";
     case Pipeline::kSeeking:
       return "seeking";
-    case Pipeline::kFlushing:
-      return "flushing";
     case Pipeline::kStarting:
       return "starting";
     case Pipeline::kStarted: