Implement getMediaDevices.

content/browser/renderer_host/media/media_stream_dispatcher_host.h

Index: content/browser/renderer_host/media/media_stream_dispatcher_host.h
diff --git a/content/browser/renderer_host/media/media_stream_dispatcher_host.h b/content/browser/renderer_host/media/media_stream_dispatcher_host.h
index 079e5dfd9ecebb28eee54cee9d52379e3878fbd8..da09af99a28f2f029724d1f62ccdcf8660945a5a 100644
--- a/content/browser/renderer_host/media/media_stream_dispatcher_host.h
+++ b/content/browser/renderer_host/media/media_stream_dispatcher_host.h
@@ -19,6 +19,7 @@
 namespace content {
 
 class MediaStreamManager;
+class ResourceContext;
 
 // MediaStreamDispatcherHost is a delegate for Media Stream API messages used by
 // MediaStreamImpl. It's the complement of MediaStreamDispatcher
@@ -29,7 +30,8 @@ class CONTENT_EXPORT MediaStreamDispatcherHost : public BrowserMessageFilter,
   MediaStreamDispatcherHost(
       int render_process_id,
       const ResourceContext::SaltCallback& salt_callback,
-      MediaStreamManager* media_stream_manager);
+      MediaStreamManager* media_stream_manager,
+      ResourceContext* resource_context);
 
   // MediaStreamRequester implementation.
   virtual void StreamGenerated(
@@ -101,6 +103,9 @@ class CONTENT_EXPORT MediaStreamDispatcherHost : public BrowserMessageFilter,
   ResourceContext::SaltCallback salt_callback_;
   MediaStreamManager* media_stream_manager_;
 
+  // Owned by ProfileIOData which is guaranteed to outlive MSDH.

[perkj_chrome, 2014/05/27 11:57:23]

I don't think this assumption is true during Chrome shutdown. See Jois cls.
Thats why ResourceContext::SaltCallback is used instead of accessing the
resource context. 

[Henrik Grunell, 2014/05/27 15:33:54]

What Cl is that?

+  ResourceContext* resource_context_;
+
   DISALLOW_COPY_AND_ASSIGN(MediaStreamDispatcherHost);
 };