cc: Remove empty viewport check in GLRenderer::BeginDrawingFrame.

cc/output/gl_renderer.cc

 // Copyright 2010 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/output/gl_renderer.h"
 
 #include <algorithm>
 #include <limits>
 #include <set>
 #include <string>
@@ skipping 453 matching lines @@
 }
 
 static ResourceProvider::ResourceId WaitOnResourceSyncPoints(
     ResourceProvider* resource_provider,
     ResourceProvider::ResourceId resource_id) {
   resource_provider->WaitSyncPointIfNeeded(resource_id);
   return resource_id;
 }
 
 void GLRenderer::BeginDrawingFrame(DrawingFrame* frame) {
-  if (frame->device_viewport_rect.IsEmpty())
-    return;
-
   TRACE_EVENT0("cc", "GLRenderer::BeginDrawingFrame");
 
   scoped_refptr<ResourceProvider::Fence> read_lock_fence;
   if (use_sync_query_) {
     // Block until oldest sync query has passed if the number of pending queries
     // ever reach kMaxPendingSyncQueries.
     if (pending_sync_queries_.size() >= kMaxPendingSyncQueries) {
       LOG(ERROR) << "Reached limit of pending sync queries.";
 
       pending_sync_queries_.front()->Wait();
@@ skipping 2879 matching lines @@
     context_support_->ScheduleOverlayPlane(
         overlay.plane_z_order,
         overlay.transform,
         pending_overlay_resources_.back()->texture_id(),
         overlay.display_rect,
         overlay.uv_rect);
   }
 }
 
 }  // namespace cc