Fix a renderer crash when media elements get deleted

webkit/media/android/webmediaplayer_android.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 "webkit/media/android/webmediaplayer_android.h"
 
 #include <string>
 
 #include "base/bind.h"
 #include "base/command_line.h"
@@ skipping 74 matching lines @@
   if (manager_)
     player_id_ = manager_->RegisterMediaPlayer(this);
   if (stream_texture_factory_.get())
     stream_texture_proxy_.reset(stream_texture_factory_->CreateProxy());
 }
 
 WebMediaPlayerAndroid::~WebMediaPlayerAndroid() {
   if (manager_)
     manager_->UnregisterMediaPlayer(player_id_);
 
+  if (stream_id_)

[Ami GONE FROM CHROMIUM, 2012/07/30 23:09:36]

Huh; I didn't realize there's only one VideoFrame in the android port (in the
media/ pipeline there are 4 in flight during playback).  Is there any reason
DestroyStreamTexture shouldn't be inlined into the dtor?
Further is there any reason the CreateStreamTexture call needs to be lazy
instead of inlining it into the ctor?  It seems like that'd be much clearer to
read...

[qinmin, 2012/07/31 22:07:52]

We had some concerns previously on memory usage of surface texture. The android
team has recently confirmed with us that no buffer will be allocated if surface
texture is not being used. So moving CreateStreamTexture to ctor makes sense
now. 
Modified the code to make stream_id_ and texture_id_ initialized in ctor, and
deletion happens in dtor. video_frame_ will be constructed once its size is
known.
On 2012/07/30 23:09:36, Ami Fischman wrote:

+     DestroyStreamTexture();
+
   if (main_loop_)
     main_loop_->RemoveDestructionObserver(this);
 }
 
 void WebMediaPlayerAndroid::InitIncognito(bool incognito_mode) {
   incognito_mode_ = incognito_mode;
 }
 
 void WebMediaPlayerAndroid::load(const WebURL& url, CORSMode cors_mode) {
   if (cors_mode != CORSModeUnspecified)
@@ skipping 431 matching lines @@
   DCHECK(!texture_id_);
   stream_id_ = stream_texture_factory_->CreateStreamTexture(&texture_id_);
   if (texture_id_)
     video_frame_.reset(new WebVideoFrameImpl(VideoFrame::WrapNativeTexture(
         texture_id_,
         kGLTextureExternalOES,
         texture_size_.width,
         texture_size_.height,
         base::TimeDelta(),
         base::TimeDelta(),
-        base::Bind(&WebMediaPlayerAndroid::DestroyStreamTexture,
-                   base::Unretained(this)))));
+        base::Closure())));
 }
 
 void WebMediaPlayerAndroid::DestroyStreamTexture() {
   DCHECK(stream_id_);
   DCHECK(texture_id_);
   stream_texture_factory_->DestroyStreamTexture(texture_id_);
   texture_id_ = 0;
   stream_id_ = 0;
 }
 
@@ skipping 16 matching lines @@
 }
 
 // This gets called both on compositor and main thread.
 void WebMediaPlayerAndroid::setStreamTextureClient(
     WebKit::WebStreamTextureClient* client) {
   if (stream_texture_proxy_.get())
     stream_texture_proxy_->SetClient(client);
 }
 
 }  // namespace webkit_media