Fix context sharing between channels to be order-independent.

Ensuring order of channel recreation after a GPU process death is very hard.
With this there's not need. A channel is either shared or not, all the "shared"
channels share their context together, every other one doesn't share with
anything. More restrictive but it's enough for our needs.

BUG=116913
TEST=chrome --ui-use-gpu-process, kill GPU process, observe GpuChannelManager::OnEstablishChannel crash doesn't happen.

Review URL: https://chromiumcodereview.appspot.com/9619017

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@125521 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 13 insertions, 7 deletions

diff --git a/content/common/gpu/gpu_channel_manager.cc b/content/common/gpu/gpu_channel_manager.cc
index 910694f..e602d43 100644
--- a/content/common/gpu/gpu_channel_manager.cc
+++ b/content/common/gpu/gpu_channel_manager.cc
@@ -9,6 +9,7 @@
 #include "content/common/gpu/gpu_channel.h"
 #include "content/common/gpu/gpu_messages.h"
 #include "content/common/gpu/gpu_memory_manager.h"
+#include "ui/gfx/gl/gl_share_group.h"
 
 GpuChannelManager::GpuChannelManager(ChildThread* gpu_child_thread,
                                      GpuWatchdog* watchdog,
@@ -82,14 +83,14 @@ bool GpuChannelManager::Send(IPC::Message* msg) {
   return gpu_child_thread_->Send(msg);
 }
 
-void GpuChannelManager::OnEstablishChannel(int client_id, int share_client_id) {
+void GpuChannelManager::OnEstablishChannel(int client_id, bool share_context) {
   IPC::ChannelHandle channel_handle;
 
   gfx::GLShareGroup* share_group = NULL;
-  if (share_client_id) {
-    GpuChannel* share_channel = gpu_channels_[share_client_id];
-    DCHECK(share_channel);
-    share_group = share_channel->share_group();
+  if (share_context) {
+    if (!share_group_)
+      share_group_ = new gfx::GLShareGroup;
+    share_group = share_group_;
   }
 
   scoped_refptr<GpuChannel> channel = new GpuChannel(this,
diff --git a/content/common/gpu/gpu_channel_manager.h b/content/common/gpu/gpu_channel_manager.h
index 01b8b7c..9fe1b26 100644
--- a/content/common/gpu/gpu_channel_manager.h
+++ b/content/common/gpu/gpu_channel_manager.h
@@ -20,6 +20,10 @@ namespace base {
 class WaitableEvent;
 }
 
+namespace gfx {
+class GLShareGroup;
+}
+
 namespace IPC {
 struct ChannelHandle;
 }
@@ -76,7 +80,7 @@ class GpuChannelManager : public IPC::Channel::Listener,
 
  private:
   // Message handlers.
-  void OnEstablishChannel(int client_id, int share_client_id);
+  void OnEstablishChannel(int client_id, bool share_context);
   void OnCloseChannel(const IPC::ChannelHandle& channel_handle);
   void OnVisibilityChanged(
       int32 render_view_id, int32 client_id, bool visible);
@@ -99,6 +103,7 @@ class GpuChannelManager : public IPC::Channel::Listener,
   // process.
   typedef base::hash_map<int, scoped_refptr<GpuChannel> > GpuChannelMap;
   GpuChannelMap gpu_channels_;
+  scoped_refptr<gfx::GLShareGroup> share_group_;
   GpuMemoryManager gpu_memory_manager_;
   GpuWatchdog* watchdog_;
 
diff --git a/content/common/gpu/gpu_messages.h b/content/common/gpu/gpu_messages.h
index 0b600ab..a8cf142 100644
--- a/content/common/gpu/gpu_messages.h
+++ b/content/common/gpu/gpu_messages.h
@@ -157,7 +157,7 @@ IPC_MESSAGE_CONTROL0(GpuMsg_Initialize)
 // This ID is a unique opaque identifier generated by the browser process.
 IPC_MESSAGE_CONTROL2(GpuMsg_EstablishChannel,
                      int /* client_id */,
-                     int /* share_client_id */)
+                     bool /* share_context */)
 
 // Tells the GPU process to close the channel identified by IPC channel
 // handle.  If no channel can be identified, do nothing.