Made Blink aware of top controls offset (Chromium-side)

cc/trees/layer_tree_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_impl.h"
 
 #include <limits>
 #include <set>
 
 #include "base/debug/trace_event.h"
@@ skipping 74 matching lines @@
       min_page_scale_factor_(0),
       max_page_scale_factor_(0),
       scrolling_layer_id_from_previous_tree_(0),
       contents_textures_purged_(false),
       requires_high_res_to_draw_(false),
       viewport_size_invalid_(false),
       needs_update_draw_properties_(true),
       needs_full_tree_sync_(true),
       next_activation_forces_redraw_(false),
       has_ever_been_drawn_(false),
-      render_surface_layer_list_id_(0) {
+      render_surface_layer_list_id_(0),
+      top_controls_content_offset_(0),
+      top_controls_delta_(0),
+      sent_top_controls_delta_(0) {
 }
 
 LayerTreeImpl::~LayerTreeImpl() {
   BreakSwapPromises(SwapPromise::SWAP_FAILS);
 
   // Need to explicitly clear the tree prior to destroying this so that
   // the LayerTreeImpl pointer is still valid in the LayerImpl dtor.
   DCHECK(!root_layer_);
   DCHECK(layers_with_copy_output_request_.empty());
 }
@@ skipping 87 matching lines @@
   // The request queue should have been processed and does not require a push.
   DCHECK_EQ(ui_resource_request_queue_.size(), 0u);
 
   if (next_activation_forces_redraw_) {
     target_tree->ForceRedrawNextActivation();
     next_activation_forces_redraw_ = false;
   }
 
   target_tree->PassSwapPromises(&swap_promise_list_);
 
+  target_tree->top_controls_content_offset_ = top_controls_content_offset_;
+  target_tree->top_controls_delta_ =
+      target_tree->top_controls_delta_ -
+          target_tree->sent_top_controls_delta_;
+  target_tree->sent_top_controls_delta_ = 0.f;
+
   target_tree->SetPageScaleValues(
       page_scale_factor(), min_page_scale_factor(), max_page_scale_factor(),
       target_tree->page_scale_delta() / target_tree->sent_page_scale_delta());
   target_tree->set_sent_page_scale_delta(1);
 
   if (page_scale_layer_ && inner_viewport_scroll_layer_) {
     target_tree->SetViewportLayersFromIds(
         page_scale_layer_->id(),
         inner_viewport_scroll_layer_->id(),
         outer_viewport_scroll_layer_ ? outer_viewport_scroll_layer_->id()
@@ skipping 156 matching lines @@
   layer->ApplySentScrollDeltasFromAbortedCommit();
 }
 
 void LayerTreeImpl::ApplySentScrollAndScaleDeltasFromAbortedCommit() {
   DCHECK(IsActiveTree());
 
   page_scale_factor_ *= sent_page_scale_delta_;
   page_scale_delta_ /= sent_page_scale_delta_;
   sent_page_scale_delta_ = 1.f;
 
+  top_controls_content_offset_ += sent_top_controls_delta_;
+  top_controls_delta_ -= sent_top_controls_delta_;
+  sent_top_controls_delta_ = 0.f;
+
   if (!root_layer())
     return;
 
   LayerTreeHostCommon::CallFunctionForSubtree(
       root_layer(), base::Bind(&ApplySentScrollDeltasFromAbortedCommitTo));
 }
 
 static void ApplyScrollDeltasSinceBeginMainFrameTo(LayerImpl* layer) {
   layer->ApplyScrollDeltasSinceBeginMainFrame();
 }
@@ skipping 1018 matching lines @@
 
 void LayerTreeImpl::UnregisterPictureLayerImpl(PictureLayerImpl* layer) {
   layer_tree_host_impl_->UnregisterPictureLayerImpl(layer);
 }
 
 void LayerTreeImpl::InputScrollAnimationFinished() {
   layer_tree_host_impl_->ScrollEnd();
 }
 
 }  // namespace cc