cc: Adding support for RGBA_4444 tile textures

gpu/command_buffer/service/async_pixel_transfer_manager_android.cc

Index: gpu/command_buffer/service/async_pixel_transfer_manager_android.cc
diff --git a/gpu/command_buffer/service/async_pixel_transfer_manager_android.cc b/gpu/command_buffer/service/async_pixel_transfer_manager_android.cc
index 8de7d58a07af2d704361313a8c92fe874f516c6d..ed12ae6735b8f2da28ddaf41a4e18035ea37e201 100644
--- a/gpu/command_buffer/service/async_pixel_transfer_manager_android.cc
+++ b/gpu/command_buffer/service/async_pixel_transfer_manager_android.cc
@@ -4,6 +4,7 @@
 
 #include "gpu/command_buffer/service/async_pixel_transfer_manager.h"
 
+#include "base/android/sys_utils.h"
 #include "base/debug/trace_event.h"
 #include "gpu/command_buffer/service/async_pixel_transfer_manager_egl.h"
 #include "gpu/command_buffer/service/async_pixel_transfer_manager_idle.h"
@@ -50,7 +51,8 @@ AsyncPixelTransferManager* AsyncPixelTransferManager::Create(
           context->HasExtension("EGL_KHR_gl_texture_2D_image") &&
           context->HasExtension("GL_OES_EGL_image") &&
           !IsBroadcom() &&
-          !IsImagination()) {
+          !IsImagination() &&
+          !base::android::SysUtils::IsLowEndDevice()) {

[piman, 2013/09/13 01:42:01]

Why is this needed here?

[kaanb, 2013/09/13 03:43:56]

See crbug.com/271929, I also added a TODO here and referenced the bug.

[piman, 2013/09/13 04:56:51]

But then it means a compromised or buggy renderer can crash the gpu process (the
browser in the android case) on a !IsLowEndDevice(). Additional code is needed
to prevent the renderer from sending 4444 data through the AsyncPixelTransfer
mechanism, to make it fail instead of crashing.

[kaanb, 2013/09/13 19:57:39]

Can you clarify what you mean by "Additional code is needed"? I checked with
epenner@ and he tells me just a DCHECK would fire when we try to send 4444 data
and DCHECKs are NOOPs in production code. 

         return new AsyncPixelTransferManagerEGL;
       }
       LOG(INFO) << "Async pixel transfers not supported";