Introduce bottom controls to CC and let it respond to scrolling

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 <stddef.h>
 #include <stdint.h>
 
 #include <algorithm>
@@ skipping 1550 matching lines @@
 CompositorFrameMetadata LayerTreeHostImpl::MakeCompositorFrameMetadata() const {
   CompositorFrameMetadata metadata;
   metadata.device_scale_factor = active_tree_->painted_device_scale_factor() *
                                  active_tree_->device_scale_factor();
 
   metadata.page_scale_factor = active_tree_->current_page_scale_factor();
   metadata.scrollable_viewport_size = active_tree_->ScrollableViewportSize();
   metadata.root_layer_size = active_tree_->ScrollableSize();
   metadata.min_page_scale_factor = active_tree_->min_page_scale_factor();
   metadata.max_page_scale_factor = active_tree_->max_page_scale_factor();
-  metadata.location_bar_offset =
-      gfx::Vector2dF(0.f, top_controls_manager_->ControlsTopOffset());
-  metadata.location_bar_content_translation =
-      gfx::Vector2dF(0.f, top_controls_manager_->ContentTopOffset());
+  metadata.top_controls_height = top_controls_manager_->TopControlsHeight();
+  metadata.top_controls_shown_ratio =
+      top_controls_manager_->TopControlsShownRatio();
+  metadata.bottom_controls_height =
+      top_controls_manager_->BottomControlsHeight();
+  metadata.bottom_controls_shown_ratio =
+      top_controls_manager_->BottomControlsShownRatio();
   metadata.root_background_color = active_tree_->background_color();
 
   active_tree_->GetViewportSelection(&metadata.selection);
 
   if (OuterViewportScrollLayer()) {
     metadata.root_overflow_x_hidden =
         !OuterViewportScrollLayer()->user_scrollable_horizontal();
     metadata.root_overflow_y_hidden =
         !OuterViewportScrollLayer()->user_scrollable_vertical();
   }
@@ skipping 275 matching lines @@
     return;
 
   ViewportAnchor anchor(InnerViewportScrollLayer(), OuterViewportScrollLayer());
 
   float top_controls_layout_height =
       active_tree_->top_controls_shrink_blink_size()
           ? active_tree_->top_controls_height()
           : 0.f;
   float delta_from_top_controls =
       top_controls_layout_height - top_controls_manager_->ContentTopOffset();
+  float bottom_controls_layout_height =
+      active_tree_->top_controls_shrink_blink_size()
+          ? active_tree_->bottom_controls_height()
+          : 0.f;
+  delta_from_top_controls += bottom_controls_layout_height -
+                             top_controls_manager_->ContentBottomOffset();
 
   // Adjust the viewport layers by shrinking/expanding the container to account
   // for changes in the size (e.g. top controls) since the last resize from
   // Blink.
   gfx::Vector2dF amount_to_expand(0.f, delta_from_top_controls);
   inner_container->SetBoundsDelta(amount_to_expand);
 
   if (outer_container && !outer_container->BoundsForScrolling().IsEmpty()) {
     // Adjust the outer viewport container as well, since adjusting only the
     // inner may cause its bounds to exceed those of the outer, causing scroll
@@ skipping 510 matching lines @@
   SetNeedsRedraw();
   SetNeedsOneBeginImplFrame();
   active_tree_->set_needs_update_draw_properties();
   SetFullRootLayerDamage();
 }
 
 float LayerTreeHostImpl::TopControlsHeight() const {
   return active_tree_->top_controls_height();
 }
 
+float LayerTreeHostImpl::BottomControlsHeight() const {
+  return active_tree_->bottom_controls_height();
+}
+
 void LayerTreeHostImpl::SetCurrentTopControlsShownRatio(float ratio) {
   if (active_tree_->SetCurrentTopControlsShownRatio(ratio))
     DidChangeTopControlsPosition();
 }
 
 float LayerTreeHostImpl::CurrentTopControlsShownRatio() const {
   return active_tree_->CurrentTopControlsShownRatio();
 }
 
 void LayerTreeHostImpl::BindToClient(InputHandlerClient* client) {
@@ skipping 1602 matching lines @@
   return task_runner_provider_->HasImplThread();
 }
 
 bool LayerTreeHostImpl::CommitToActiveTree() const {
   // In single threaded mode we skip the pending tree and commit directly to the
   // active tree.
   return !task_runner_provider_->HasImplThread();
 }
 
 }  // namespace cc