Implement transform/clip support for Android WebView.

cc/trees/layer_tree_host_impl.cc

 // Copyright 2011 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/trees/layer_tree_host_impl.h"
 
 #include <algorithm>
 
 #include "base/basictypes.h"
 #include "base/json/json_writer.h"
@@ skipping 1017 matching lines @@
     EnforceManagedMemoryPolicy(ActualManagedMemoryPolicy());
   } else {
     DCHECK(proxy_->IsImplThread());
     EnforceManagedMemoryPolicy(ActualManagedMemoryPolicy());
   }
 
   if (needs_commit)
     client_->SetNeedsCommitOnImplThread();
 }
 
+void LayerTreeHostImpl::SetDeviceTransformAndClip(
+    const gfx::Transform& transform,
+    gfx::Rect clip) {
+  device_transform_ = transform;
+  device_clip_ = clip;
+}
+
 void LayerTreeHostImpl::SetNeedsRedrawRect(gfx::Rect damage_rect) {
   client_->SetNeedsRedrawRectOnImplThread(damage_rect);
 }
 
 void LayerTreeHostImpl::OnVSyncParametersChanged(base::TimeTicks timebase,
                                                  base::TimeDelta interval) {
   client_->OnVSyncParametersChanged(timebase, interval);
 }
 
 void LayerTreeHostImpl::BeginFrame(base::TimeTicks frame_time) {
@@ skipping 461 matching lines @@
 
 void LayerTreeHostImpl::SetDeviceScaleFactor(float device_scale_factor) {
   if (device_scale_factor == device_scale_factor_)
     return;
   device_scale_factor_ = device_scale_factor;
 
   UpdateMaxScrollOffset();
   SetFullRootLayerDamage();
 }
 
+gfx::Rect LayerTreeHostImpl::DeviceClip() const {
+  if (device_clip_.IsEmpty())
+    return gfx::Rect(device_viewport_size_);
+
+  return device_clip_;
+}
+
+gfx::Transform LayerTreeHostImpl::DeviceTransform() const {
+  gfx::Transform device_transform = device_transform_;
+  device_transform.Scale(device_scale_factor_, device_scale_factor_);
+  return device_transform;
+}
+
+gfx::Vector2d LayerTreeHostImpl::DeviceViewportOffset() const {
+  return gfx::Vector2d(device_clip_.x(), device_clip_.y());
+}
+
 void LayerTreeHostImpl::UpdateMaxScrollOffset() {
   active_tree_->UpdateMaxScrollOffset();
 }
 
 void LayerTreeHostImpl::DidChangeTopControlsPosition() {
   client_->SetNeedsRedrawOnImplThread();
   active_tree_->set_needs_update_draw_properties();
   SetFullRootLayerDamage();
 }
 
@@ skipping 707 matching lines @@
 }
 
 void LayerTreeHostImpl::SetDebugState(const LayerTreeDebugState& debug_state) {
   if (debug_state_.continuous_painting != debug_state.continuous_painting)
     paint_time_counter_->ClearHistory();
 
   debug_state_ = debug_state;
 }
 
 }  // namespace cc