gpu: Reuse transfer buffers more aggresively

gpu/command_buffer/service/async_pixel_transfer_manager_share_group.cc

Index: gpu/command_buffer/service/async_pixel_transfer_manager_share_group.cc
diff --git a/gpu/command_buffer/service/async_pixel_transfer_manager_share_group.cc b/gpu/command_buffer/service/async_pixel_transfer_manager_share_group.cc
index dcdab1c69adb5dd2a4c9be58a9351ece0b258849..d2061e8ee4fcf2d36ba661963b148241e5e47c4b 100644
--- a/gpu/command_buffer/service/async_pixel_transfer_manager_share_group.cc
+++ b/gpu/command_buffer/service/async_pixel_transfer_manager_share_group.cc
@@ -573,6 +573,16 @@ bool AsyncPixelTransferManagerShareGroup::NeedsProcessMorePendingTransfers() {
   return false;
 }
 
+void AsyncPixelTransferManagerShareGroup::WaitAllAsyncTexImage2D() {
+  if (shared_state_.pending_allocations.empty())
+    return;
+
+  AsyncPixelTransferDelegateShareGroup* delegate =
+      shared_state_.pending_allocations.back().get();
+  if (delegate)
+    delegate->WaitForTransferCompletion();
+}
+
 AsyncPixelTransferDelegate*
 AsyncPixelTransferManagerShareGroup::CreatePixelTransferDelegateImpl(
     gles2::TextureRef* ref,