Plumbing: Cache the resize callback so that we can call it later.

I am working towards having two surfaces that the GpuScheduler alternates between on SwapBuffers. Each surface should be resized once it is the backbuffer (via SwapBuffers). By caching the resize callback, I can (a) resize of the backbuffer immediately when the callback is initiated from the GLES2Decoder and (b) resize the frontbuffer once it becomes the backbuffer after a SwapBuffers.

BUG=none
TEST=none (should be no-op on all platforms)

Review URL: http://codereview.chromium.org/6982060

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@88327 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 15 insertions, 1 deletions

diff --git a/gpu/command_buffer/service/gpu_scheduler.cc b/gpu/command_buffer/service/gpu_scheduler.cc
index 5fa9ceb..53fcfa2 100644
--- a/gpu/command_buffer/service/gpu_scheduler.cc
+++ b/gpu/command_buffer/service/gpu_scheduler.cc
@@ -276,7 +276,10 @@ void GpuScheduler::ResizeOffscreenFrameBuffer(const gfx::Size& size) {
 }
 
 void GpuScheduler::SetResizeCallback(Callback1<gfx::Size>::Type* callback) {
-  decoder_->SetResizeCallback(callback);
+  wrapped_resize_callback_.reset(callback);
+  decoder_->SetResizeCallback(
+      NewCallback(this,
+                  &GpuScheduler::WillResize));
 }
 
 void GpuScheduler::SetSwapBuffersCallback(
@@ -298,4 +301,10 @@ void GpuScheduler::ScheduleProcessCommands() {
       method_factory_.NewRunnableMethod(&GpuScheduler::ProcessCommands));
 }
 
+void GpuScheduler::WillResize(gfx::Size size) {
+  if (wrapped_resize_callback_.get()) {
+    wrapped_resize_callback_->Run(size);
+  }
+}
+
 }  // namespace gpu
diff --git a/gpu/command_buffer/service/gpu_scheduler.h b/gpu/command_buffer/service/gpu_scheduler.h
index b49713f..7f74734 100644
--- a/gpu/command_buffer/service/gpu_scheduler.h
+++ b/gpu/command_buffer/service/gpu_scheduler.h
@@ -160,6 +160,10 @@ class GpuScheduler : public CommandBufferEngine {
   void ScheduleProcessCommands();
 
   // Called via a callback just before we are supposed to call the
+  // user's resize callback.
+  void WillResize(gfx::Size size);
+
+  // Called via a callback just before we are supposed to call the
   // user's swap buffers callback.
   void WillSwapBuffers();
   void ProcessCommands();
@@ -186,6 +190,7 @@ class GpuScheduler : public CommandBufferEngine {
 #endif
 
   ScopedRunnableMethodFactory<GpuScheduler> method_factory_;
+  scoped_ptr<Callback1<gfx::Size>::Type> wrapped_resize_callback_;
   scoped_ptr<Callback0::Type> wrapped_swap_buffers_callback_;
   scoped_ptr<Callback0::Type> command_processed_callback_;
 };