Revert 142541 - Drop frontbuffers with ui-use-gpu-process, synchronized with browser, decoupled from backbuffer drop.

Reason (speculative):
According to http://build.chromium.org/p/chromium.chromiumos/builders/ChromiumOS%20%28amd64%29/builds/2556
http://build.chromium.org/p/chromium.chromiumos/builders/ChromiumOS%20%28x86%29/builds/6039

after this commit those bots startet faling VMTest stage.

On Aura, every time a tab is backgrounded, RenderWidgetHostViewAura will reset its handle to the front surface.  If that tab is foregrounded again, that front surface will not be used until synchronizing with the gpu process to make sure that surface is still available.  By doing this, the gpu process knows when it is safe to discard the front surface.

RWHVA sends a FrontSurfaceIsProtected(bool, int) message to the gpu process to keep it informed about front surface protection.  The int is a state-of-the-world identifier to protect from ABA issues.  RWHVA delays sending FrontSurfaceIsProtected(false) until after the current surface is certain to not be in use, namely after the compositor finishes the current frame and the browser thumbnailer is complete.


BUG=112842
TEST=Manual


Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=142408

Review URL: https://chromiumcodereview.appspot.com/10052018

TBR=mmocny@chromium.org
Review URL: https://chromiumcodereview.appspot.com/10563021

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@142692 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 0 insertions, 4 deletions

diff --git a/content/common/gpu/image_transport_surface.h b/content/common/gpu/image_transport_surface.h
index 936f40d..019aa50 100644
--- a/content/common/gpu/image_transport_surface.h
+++ b/content/common/gpu/image_transport_surface.h
@@ -67,8 +67,6 @@ class ImageTransportSurface {
   virtual void OnPostSubBufferACK() = 0;
   virtual void OnResizeViewACK() = 0;
   virtual void OnResize(gfx::Size size) = 0;
-  virtual void OnSetFrontSurfaceIsProtected(bool is_protected,
-                                            uint32 protection_state_id);
 
   // Creates the appropriate surface depending on the GL implementation.
   static scoped_refptr<gfx::GLSurface>
@@ -140,8 +138,6 @@ class ImageTransportHelper : public IPC::Channel::Listener {
   void OnBuffersSwappedACK();
   void OnPostSubBufferACK();
   void OnResizeViewACK();
-  void OnSetFrontSurfaceIsProtected(bool is_protected,
-                                    uint32 protection_state_id);
 
   // Backbuffer resize callback.
   void Resize(gfx::Size size);