Revert of Move AW renderer compositor context to gpu thread

gpu/command_buffer/service/async_pixel_transfer_manager_idle.cc

Index: gpu/command_buffer/service/async_pixel_transfer_manager_idle.cc
diff --git a/gpu/command_buffer/service/async_pixel_transfer_manager_idle.cc b/gpu/command_buffer/service/async_pixel_transfer_manager_idle.cc
index b44b4774046e9995963009cb5214b1e449f5a05f..2ed4f7d9d04a1b9823b5b0344f8441296ebf7e53 100644
--- a/gpu/command_buffer/service/async_pixel_transfer_manager_idle.cc
+++ b/gpu/command_buffer/service/async_pixel_transfer_manager_idle.cc
@@ -183,8 +183,9 @@
   base::TimeTicks begin_time(base::TimeTicks::Now());
   gfx::ScopedTextureBinder texture_binder(tex_params.target, texture_id_);
 
-  if (shared_state_->use_teximage2d_over_texsubimage2d &&
-      tex_params.xoffset == 0 &&
+  // If it's a full texture update, use glTexImage2D as it's faster.
+  // TODO(epenner): Make this configurable (http://crbug.com/259924)
+  if (tex_params.xoffset == 0 &&
       tex_params.yoffset == 0 &&
       tex_params.target == define_params_.target &&
       tex_params.level  == define_params_.level &&
@@ -233,11 +234,8 @@
 
 AsyncPixelTransferManagerIdle::Task::~Task() {}
 
-AsyncPixelTransferManagerIdle::SharedState::SharedState(
-    bool use_teximage2d_over_texsubimage2d)
-    : use_teximage2d_over_texsubimage2d(use_teximage2d_over_texsubimage2d),
-      texture_upload_count(0) {
-}
+AsyncPixelTransferManagerIdle::SharedState::SharedState()
+    : texture_upload_count(0) {}
 
 AsyncPixelTransferManagerIdle::SharedState::~SharedState() {}
 
@@ -252,9 +250,8 @@
   }
 }
 
-AsyncPixelTransferManagerIdle::AsyncPixelTransferManagerIdle(
-    bool use_teximage2d_over_texsubimage2d)
-    : shared_state_(use_teximage2d_over_texsubimage2d) {
+AsyncPixelTransferManagerIdle::AsyncPixelTransferManagerIdle()
+  : shared_state_() {
 }
 
 AsyncPixelTransferManagerIdle::~AsyncPixelTransferManagerIdle() {}