Directly call ChunkDemuxer::Initialize completion callback.

media/filters/chunk_demuxer.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "media/filters/chunk_demuxer.h"
 
 #include <algorithm>
 #include <limits>
 #include <list>
 #include <utility>
@@ skipping 407 matching lines @@
       detected_video_track_count_(0),
       detected_text_track_count_(0) {
   DCHECK(!open_cb_.is_null());
   DCHECK(!encrypted_media_init_data_cb_.is_null());
 }
 
 std::string ChunkDemuxer::GetDisplayName() const {
   return "ChunkDemuxer";
 }
 
-void ChunkDemuxer::Initialize(
-    DemuxerHost* host,
-    const PipelineStatusCB& cb,
-    bool enable_text_tracks) {
+void ChunkDemuxer::Initialize(DemuxerHost* host,
+                              const PipelineStatusCB& init_cb,
+                              bool enable_text_tracks) {
   DVLOG(1) << "Init()";
 
   base::AutoLock auto_lock(lock_);
-
-  // The |init_cb_| must only be run after this method returns, so always post.
-  init_cb_ = BindToCurrentLoop(cb);
   if (state_ == SHUTDOWN) {
-    base::ResetAndReturn(&init_cb_).Run(DEMUXER_ERROR_COULD_NOT_OPEN);
+    // Init cb must only be run after this method returns, so always post.

[wolenetz, 2016/09/23 00:11:46]

nit: s/always//

[alokp, 2016/09/28 17:22:45]

Done.

+    base::ThreadTaskRunnerHandle::Get()->PostTask(
+        FROM_HERE, base::Bind(init_cb, DEMUXER_ERROR_COULD_NOT_OPEN));
     return;
   }
+
   DCHECK_EQ(state_, WAITING_FOR_INIT);
   host_ = host;
+  // Do not post init_cb once this function returns because if there is an
+  // error after initialization, the error might be reported before init_cb
+  // has a chance to run. This is because ChunkDemuxer::ReportError_Locked
+  // directly calls DemuxerHost::OnDemuxerError: crbug.com/633016.
+  init_cb_ = init_cb;
   enable_text_ = enable_text_tracks;
 
   ChangeState_Locked(INITIALIZING);
 
   base::ResetAndReturn(&open_cb_).Run();
 }
 
 void ChunkDemuxer::Stop() {
   DVLOG(1) << "Stop()";
   Shutdown();
@@ skipping 569 matching lines @@
 
     ShutdownAllStreams();
   }
 
   if (!cb.is_null()) {
     cb.Run(error);
     return;
   }
 
   base::AutoUnlock auto_unlock(lock_);
   host_->OnDemuxerError(error);

[wolenetz, 2016/09/23 00:11:46]

Doesn't the host trampoline this back to the media thread? ReportError_Locked is
run on the render main thread from what I can tell. So is OnSourceInitDone.

So, IIUC, without this CL, init_cb_ gets bound to media thread and posted there
from this class in all of its usages (even in ::Initialize()). And in error case
shortly after init_cb_ is posted, OnDemuxerError trampolines to media thread, so
the ordering should be maintained. Other than unit tests, which might insert
their own OnDemuxerError which *doesn't* trampoline, where does this currently
fail?

[wolenetz, 2016/09/27 21:01:14]

Ignore (see my previous reply on the CL message thread).

[alokp, 2016/09/28 17:22:45]

Acknowledged.

 }
 
 bool ChunkDemuxer::IsSeekWaitingForData_Locked() const {
   lock_.AssertAcquired();
   for (MediaSourceStateMap::const_iterator itr = source_state_map_.begin();
        itr != source_state_map_.end(); ++itr) {
     if (itr->second->IsSeekWaitingForData())
       return true;
   }
 
@@ skipping 228 matching lines @@
 }
 
 void ChunkDemuxer::ShutdownAllStreams() {
   for (MediaSourceStateMap::iterator itr = source_state_map_.begin();
        itr != source_state_map_.end(); ++itr) {
     itr->second->Shutdown();
   }
 }
 
 }  // namespace media