Android WebView: Fall back to idle uploads if draw functor table not set

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 ba1ad2e41936d65636c4801e5a86c8bf8c9644ff..618bd0e9538101f613296036c8edcffa73b7b19d 100644
--- a/gpu/command_buffer/service/async_pixel_transfer_manager_android.cc
+++ b/gpu/command_buffer/service/async_pixel_transfer_manager_android.cc
@@ -10,6 +10,7 @@
 #include "gpu/command_buffer/service/async_pixel_transfer_manager_idle.h"
 #include "gpu/command_buffer/service/async_pixel_transfer_manager_stub.h"
 #include "gpu/command_buffer/service/async_pixel_transfer_manager_sync.h"
+#include "gpu/command_buffer/service/mailbox_synchronizer.h"
 #include "ui/gl/gl_context.h"
 #include "ui/gl/gl_implementation.h"
 
@@ -63,7 +64,8 @@ AsyncPixelTransferManager* AsyncPixelTransferManager::Create(
           !IsBroadcom() &&
           !IsImagination() &&
           !IsNvidia31() &&
-          !base::SysInfo::IsLowEndDevice()) {
+          !base::SysInfo::IsLowEndDevice() &&
+          !gles2::MailboxSynchronizer::GetInstance()) {

[boliu, 2014/07/24 01:29:07]

What does the rest of this change have to do with MailboxSynchronizer? That's
initialized in aw_browser_main_parts.cc

[no sievers, 2014/07/24 16:59:39]

This async upload impl does not work with mailbox sync because it creates EGL
images for the textures also.
Disabling it here makes it fall back to the idle uploader.

[boliu, 2014/07/24 17:00:59]

I don't see how the functor table not being set leads to MailboxSynchronizer not
being initialized though.

[no sievers, 2014/07/24 19:21:26]

It has nothing to do with the draw functor table.
The draw functor table not being set falls back to async uploads.
MailboxSync enabled disallows AsyncPixelTransferManagerEGL.

[boliu, 2014/07/24 20:50:24]

Oh...that wasn't obvious

         return new AsyncPixelTransferManagerEGL;
       }
       return new AsyncPixelTransferManagerIdle;