Cleanup resourceless_software_draw()

content/browser/android/in_process/synchronous_compositor_output_surface.cc

 // Copyright 2013 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 "content/browser/android/in_process/synchronous_compositor_output_surface.h"
 
 #include "base/auto_reset.h"
 #include "base/logging.h"
 #include "cc/output/begin_frame_args.h"
 #include "cc/output/compositor_frame.h"
@@ skipping 182 matching lines @@
   SkIRect canvas_clip;
   canvas->getClipDeviceBounds(&canvas_clip);
   gfx::Rect clip = gfx::SkIRectToRect(canvas_clip);
 
   gfx::Transform transform(gfx::Transform::kSkipInitialization);
   transform.matrix() = canvas->getTotalMatrix();  // Converts 3x3 matrix to 4x4.
 
   surface_size_ = gfx::Size(canvas->getDeviceSize().width(),
                             canvas->getDeviceSize().height());
 
-  // Resourceless software draw does not need viewport_for_tiling.
-  gfx::Rect empty;
-  InvokeComposite(transform, clip, clip, empty, gfx::Transform(), false);
+  // Pass in the cached hw viewport and transform for tile priority to avoid
+  // tile thrashing when the WebView is alternating between hardware and
+  // software draws.
+  InvokeComposite(transform,
+                  clip,
+                  clip,
+                  cached_hw_viewport_rect_for_tile_priority_,
+                  cached_hw_transform_for_tile_priority_,
+                  false);
 
   return frame_holder_.Pass();
 }
 
 void SynchronousCompositorOutputSurface::InvokeComposite(
     const gfx::Transform& transform,
     gfx::Rect viewport,
     gfx::Rect clip,
     gfx::Rect viewport_rect_for_tile_priority,
     gfx::Transform transform_for_tile_priority,
@@ skipping 70 matching lines @@
 bool SynchronousCompositorOutputSurface::CalledOnValidThread() const {
   return BrowserThread::CurrentlyOn(BrowserThread::UI);
 }
 
 SynchronousCompositorOutputSurfaceDelegate*
 SynchronousCompositorOutputSurface::GetDelegate() {
   return SynchronousCompositorImpl::FromRoutingID(routing_id_);
 }
 
 }  // namespace content