Added more detailed result codes for CreateViewCommandBuffer.

content/browser/gpu/gpu_process_host.cc

Index: content/browser/gpu/gpu_process_host.cc
diff --git a/content/browser/gpu/gpu_process_host.cc b/content/browser/gpu/gpu_process_host.cc
index ad709972b18da004951e06a9f27ffb2321944633..6ab7994ed981a4cc980d13de0c8bc8db2d0603b2 100644
--- a/content/browser/gpu/gpu_process_host.cc
+++ b/content/browser/gpu/gpu_process_host.cc
@@ -646,7 +646,9 @@ void GpuProcessHost::CreateViewCommandBuffer(
     surface_refs_.insert(std::make_pair(surface_id,
         GpuSurfaceTracker::GetInstance()->GetSurfaceRefForSurface(surface_id)));
   } else {
-    callback.Run(false);
+    // Could distinguish here between compositing_surface being NULL
+    // and Send failing, if desired.

[piman, 2014/07/11 23:20:09]

Really, we should assert and fix it upstream

+    callback.Run(CREATE_CMDBUF_FAILED_AND_CHANNEL_LOST);
   }
 }
 
@@ -754,7 +756,7 @@ void GpuProcessHost::OnCommandBufferCreated(bool succeeded) {
   CreateCommandBufferCallback callback =
       create_command_buffer_requests_.front();
   create_command_buffer_requests_.pop();
-  callback.Run(succeeded);
+  callback.Run(succeeded ? CREATE_CMDBUF_SUCCEEDED : CREATE_CMDBUF_FAILED);

[piman, 2014/07/11 23:20:09]

ideally we'd pass a CreateCommandBufferResult back from the GPU process. Looking
at it currently the only reason this fails is if the client messed up its
routing id allocation (or is malicious), or it wrapeed around and we collided...
should we cause a CHANNEL_LOST in that case? We might be able to recover
slightly better.

[Ken Russell (switch to Gerrit), 2014/07/12 00:44:52]

Thanks, that sounds cleaner. I've implemented this.

 }
 
 void GpuProcessHost::OnDestroyCommandBuffer(int32 surface_id) {
@@ -1061,7 +1063,7 @@ void GpuProcessHost::SendOutstandingReplies() {
     CreateCommandBufferCallback callback =
         create_command_buffer_requests_.front();
     create_command_buffer_requests_.pop();
-    callback.Run(false);
+    callback.Run(CREATE_CMDBUF_FAILED_AND_CHANNEL_LOST);
   }
 }