Update from https://crrev.com/306901

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 <limits>
 
 #include "base/basictypes.h"
@@ skipping 219 matching lines @@
       requires_high_res_to_draw_(false),
       required_for_draw_tile_is_top_of_raster_queue_(false) {
   DCHECK(proxy_->IsImplThread());
   DidVisibilityChange(this, visible_);
   animation_registrar_->set_supports_scroll_animations(
       proxy_->SupportsImplScrolling());
 
   SetDebugState(settings.initial_debug_state);
 
   // LTHI always has an active tree.
-  active_tree_ = LayerTreeImpl::create(this);
+  active_tree_ = LayerTreeImpl::create(this, new SyncedProperty<ScaleGroup>());
+
   TRACE_EVENT_OBJECT_CREATED_WITH_ID(
       TRACE_DISABLED_BY_DEFAULT("cc.debug"), "cc::LayerTreeHostImpl", id_);
 
   if (settings.calculate_top_controls_position) {
     top_controls_manager_ =
         TopControlsManager::Create(this,
-                                   settings.top_controls_height,
                                    settings.top_controls_show_threshold,
                                    settings.top_controls_hide_threshold);
-
-    // TODO(bokan): This is a quick fix. The browser should lock the top
-    // controls to shown on creation but this appears not to work. Tracked
-    // in crbug.com/417680.
-    // Initialize with top controls showing.
-    SetControlsTopOffset(0.f);
   }
 }
 
 LayerTreeHostImpl::~LayerTreeHostImpl() {
   DCHECK(proxy_->IsImplThread());
   TRACE_EVENT0("cc", "LayerTreeHostImpl::~LayerTreeHostImpl()");
   TRACE_EVENT_OBJECT_DELETED_WITH_ID(
       TRACE_DISABLED_BY_DEFAULT("cc.debug"), "cc::LayerTreeHostImpl", id_);
 
   if (input_handler_client_) {
@@ skipping 144 matching lines @@
   gfx::ScrollOffset scroll_total = active_tree_->TotalScrollOffset();
   gfx::SizeF scaled_scrollable_size = active_tree_->ScrollableSize();
   gfx::SizeF viewport_size =
       active_tree_->InnerViewportContainerLayer()->bounds();
 
   // Easing constants experimentally determined.
   scoped_ptr<TimingFunction> timing_function =
       CubicBezierTimingFunction::Create(.8, 0, .3, .9);
 
   // TODO(miletus) : Pass in ScrollOffset.
-  page_scale_animation_ =
-      PageScaleAnimation::Create(ScrollOffsetToVector2dF(scroll_total),
-                                 active_tree_->total_page_scale_factor(),
-                                 viewport_size,
-                                 scaled_scrollable_size,
-                                 timing_function.Pass());
+  page_scale_animation_ = PageScaleAnimation::Create(
+      ScrollOffsetToVector2dF(scroll_total),
+      active_tree_->current_page_scale_factor(), viewport_size,
+      scaled_scrollable_size, timing_function.Pass());
 
   if (anchor_point) {
     gfx::Vector2dF anchor(target_offset);
     page_scale_animation_->ZoomWithAnchor(anchor,
                                           page_scale,
                                           duration.InSecondsF());
   } else {
     gfx::Vector2dF scaled_target_offset = target_offset;
     page_scale_animation_->ZoomTo(scaled_target_offset,
                                   page_scale,
@@ skipping 232 matching lines @@
         false,
         gfx::PointF(
             screen_space_rect.x() / overhang_resource_scaled_size.width(),
             screen_space_rect.y() / overhang_resource_scaled_size.height()),
         gfx::PointF(
             screen_space_rect.right() / overhang_resource_scaled_size.width(),
             screen_space_rect.bottom() /
                 overhang_resource_scaled_size.height()),
         screen_background_color,
         vertex_opacity,
+        false,
         false);
   }
 }
 
 DrawResult LayerTreeHostImpl::CalculateRenderPasses(
     FrameData* frame) {
   DCHECK(frame->render_passes.empty());
   DCHECK(CanDraw());
   DCHECK(active_tree_->root_layer());
 
@@ skipping 413 matching lines @@
   EnforceManagedMemoryPolicy(ManagedMemoryPolicy(0));
 }
 
 void LayerTreeHostImpl::BlockNotifyReadyToActivateForTesting(bool block) {
   NOTREACHED();
 }
 
 void LayerTreeHostImpl::ResetTreesForTesting() {
   if (active_tree_)
     active_tree_->DetachLayerTree();
-  active_tree_ = LayerTreeImpl::create(this);
+  active_tree_ =
+      LayerTreeImpl::create(this, active_tree()->page_scale_factor());
   if (pending_tree_)
     pending_tree_->DetachLayerTree();
   pending_tree_ = nullptr;
   if (recycle_tree_)
     recycle_tree_->DetachLayerTree();
   recycle_tree_ = nullptr;
 }
 
 void LayerTreeHostImpl::EnforceManagedMemoryPolicy(
     const ManagedMemoryPolicy& policy) {
@@ skipping 303 matching lines @@
   }
 }
 
 void LayerTreeHostImpl::OnCanDrawStateChangedForTree() {
   client_->OnCanDrawStateChanged(CanDraw());
 }
 
 CompositorFrameMetadata LayerTreeHostImpl::MakeCompositorFrameMetadata() const {
   CompositorFrameMetadata metadata;
   metadata.device_scale_factor = device_scale_factor_;
-  metadata.page_scale_factor = active_tree_->total_page_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();
   if (top_controls_manager_) {
     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());
   }
@@ skipping 208 matching lines @@
   LayerImpl* outer_container = active_tree_->OuterViewportContainerLayer();
 
   if (!inner_container || !top_controls_manager_)
     return;
 
   ViewportAnchor anchor(InnerViewportScrollLayer(),
                         OuterViewportScrollLayer());
 
   // Adjust the inner viewport by shrinking/expanding the container to account
   // for the change in top controls height since the last Resize from Blink.
+  float top_controls_layout_height =
+      active_tree_->top_controls_shrink_blink_size()
+          ? active_tree_->top_controls_height()
+          : 0.f;
   inner_container->SetBoundsDelta(
-      gfx::Vector2dF(0, active_tree_->top_controls_layout_height() -
-          active_tree_->total_top_controls_content_offset()));
+      gfx::Vector2dF(0, top_controls_layout_height -
+                            active_tree_->total_top_controls_content_offset()));
 
   if (!outer_container || outer_container->BoundsForScrolling().IsEmpty())
     return;
 
   // Adjust the outer viewport container as well, since adjusting only the
   // inner may cause its bounds to exceed those of the outer, causing scroll
   // clamping. We adjust it so it maintains the same aspect ratio as the
   // inner viewport.
   float aspect_ratio = inner_container->BoundsForScrolling().width() /
       inner_container->BoundsForScrolling().height();
   float target_height = outer_container->BoundsForScrolling().width() /
       aspect_ratio;
   float current_outer_height = outer_container->BoundsForScrolling().height() -
       outer_container->bounds_delta().y();
   gfx::Vector2dF delta(0, target_height - current_outer_height);
 
   outer_container->SetBoundsDelta(delta);
   active_tree_->InnerViewportScrollLayer()->SetBoundsDelta(delta);
 
   anchor.ResetViewportToAnchoredPosition();
 }
 
-void LayerTreeHostImpl::SetTopControlsLayoutHeight(float height) {
-  if (active_tree_->top_controls_layout_height() == height)
-    return;
-
-  active_tree_->set_top_controls_layout_height(height);
-  UpdateViewportContainerSizes();
-  SetFullRootLayerDamage();
-}
-
 void LayerTreeHostImpl::SynchronouslyInitializeAllTiles() {
   // Only valid for the single-threaded non-scheduled/synchronous case
   // using the zero copy raster worker pool.
   single_thread_synchronous_task_graph_runner_->RunUntilIdle();
 }
 
 void LayerTreeHostImpl::DidLoseOutputSurface() {
   if (resource_provider_)
     resource_provider_->DidLoseOutputSurface();
   client_->DidLoseOutputSurfaceOnImplThread();
@@ skipping 43 matching lines @@
     return layer_impl->parent();
 
   return NULL;
 }
 
 void LayerTreeHostImpl::CreatePendingTree() {
   CHECK(!pending_tree_);
   if (recycle_tree_)
     recycle_tree_.swap(pending_tree_);
   else
-    pending_tree_ = LayerTreeImpl::create(this);
+    pending_tree_ =
+        LayerTreeImpl::create(this, active_tree()->page_scale_factor());
 
   // Update the delta from the active tree, which may have
   // adjusted its delta prior to the pending tree being created.
-  DCHECK_EQ(1.f, pending_tree_->sent_page_scale_delta());
   DCHECK_EQ(0.f, pending_tree_->sent_top_controls_delta());
-  pending_tree_->SetPageScaleDelta(active_tree_->page_scale_delta() /
-                                   active_tree_->sent_page_scale_delta());
   pending_tree_->set_top_controls_delta(
       active_tree_->top_controls_delta() -
       active_tree_->sent_top_controls_delta());
+  pending_tree_->set_top_controls_height(active_tree_->top_controls_height());
 
   client_->OnCanDrawStateChanged(CanDraw());
   TRACE_EVENT_ASYNC_BEGIN0("cc", "PendingTree:waiting", pending_tree_.get());
 }
 
 void LayerTreeHostImpl::ActivateSyncTree() {
   if (pending_tree_) {
     TRACE_EVENT_ASYNC_END0("cc", "PendingTree:waiting", pending_tree_.get());
 
     active_tree_->SetRootLayerScrollOffsetDelegate(NULL);
@@ skipping 16 matching lines @@
     // Now that we've synced everything from the pending tree to the active
     // tree, rename the pending tree the recycle tree so we can reuse it on the
     // next sync.
     DCHECK(!recycle_tree_);
     pending_tree_.swap(recycle_tree_);
 
     active_tree_->SetRootLayerScrollOffsetDelegate(
         root_layer_scroll_offset_delegate_);
 
     if (top_controls_manager_) {
+      top_controls_manager_->SetTopControlsHeight(
+          active_tree_->top_controls_height());
       top_controls_manager_->SetControlsTopOffset(
           active_tree_->total_top_controls_content_offset() -
-          top_controls_manager_->top_controls_height());
+          active_tree_->top_controls_height());
     }
 
     UpdateViewportContainerSizes();
   } else {
     active_tree_->ProcessUIResourceRequestQueue();
   }
 
   active_tree_->DidBecomeActive();
   ActivateAnimations();
   if (settings_.impl_side_painting)
@@ skipping 404 matching lines @@
 }
 
 void LayerTreeHostImpl::SetDeviceScaleFactor(float device_scale_factor) {
   if (device_scale_factor == device_scale_factor_)
     return;
   device_scale_factor_ = device_scale_factor;
 
   SetFullRootLayerDamage();
 }
 
+void LayerTreeHostImpl::SetPageScaleOnActiveTree(float page_scale_factor) {
+  active_tree_->SetPageScaleOnActiveTree(page_scale_factor);
+}
+
 const gfx::Rect LayerTreeHostImpl::ViewportRectForTilePriority() const {
   if (viewport_rect_for_tile_priority_.IsEmpty())
     return DeviceViewport();
 
   return viewport_rect_for_tile_priority_;
 }
 
 gfx::Size LayerTreeHostImpl::DrawViewportSize() const {
   return DeviceViewport().size();
 }
@@ skipping 19 matching lines @@
 void LayerTreeHostImpl::DidChangeTopControlsPosition() {
   UpdateViewportContainerSizes();
   SetNeedsRedraw();
   SetNeedsAnimate();
   active_tree_->set_needs_update_draw_properties();
   SetFullRootLayerDamage();
 }
 
 void LayerTreeHostImpl::SetControlsTopOffset(float offset) {
   float current_top_offset = active_tree_->top_controls_content_offset() -
-      top_controls_manager_->top_controls_height();
+                             active_tree_->top_controls_height();
   active_tree_->set_top_controls_delta(offset - current_top_offset);
 }
 
 float LayerTreeHostImpl::ControlsTopOffset() const {
   return active_tree_->total_top_controls_content_offset() -
-      top_controls_manager_->top_controls_height();
+         active_tree_->top_controls_height();
 }
 
 void LayerTreeHostImpl::BindToClient(InputHandlerClient* client) {
   DCHECK(input_handler_client_ == NULL);
   input_handler_client_ = client;
 }
 
 static LayerImpl* NextScrollLayer(LayerImpl* layer) {
   if (LayerImpl* scroll_parent = layer->scroll_parent())
     return scroll_parent;
@@ skipping 349 matching lines @@
     // scrolling so we can just apply them directly, but the page scale factor
     // is applied to the scroll delta.
     if (!wheel_scrolling_) {
       float scale_from_viewport_to_screen_space = device_scale_factor_;
       applied_delta =
           ScrollLayerWithViewportSpaceDelta(layer_impl,
                                             scale_from_viewport_to_screen_space,
                                             viewport_point, pending_delta);
     } else {
       applied_delta = ScrollLayerWithLocalDelta(
-          layer_impl, pending_delta, active_tree_->total_page_scale_factor());
+          layer_impl, pending_delta, active_tree_->current_page_scale_factor());
     }
 
     const float kEpsilon = 0.1f;
     if (layer_impl == InnerViewportScrollLayer()) {
       unused_root_delta.Subtract(applied_delta);
       if (std::abs(unused_root_delta.x()) < kEpsilon)
         unused_root_delta.set_x(0.0f);
       if (std::abs(unused_root_delta.y()) < kEpsilon)
         unused_root_delta.set_y(0.0f);
       // Disable overscroll on axes which is impossible to scroll.
@@ skipping 283 matching lines @@
 
   TRACE_EVENT0("cc", "LayerTreeHostImpl::PinchGestureUpdate");
 
   // For a moment the scroll offset ends up being outside of the max range. This
   // confuses the delegate so we switch it off till after we're done processing
   // the pinch update.
   active_tree_->SetRootLayerScrollOffsetDelegate(NULL);
 
   // Keep the center-of-pinch anchor specified by (x, y) in a stable
   // position over the course of the magnify.
-  float page_scale_delta = active_tree_->page_scale_delta();
-  gfx::PointF previous_scale_anchor =
-      gfx::ScalePoint(anchor, 1.f / page_scale_delta);
-  active_tree_->SetPageScaleDelta(page_scale_delta * magnify_delta);
-  page_scale_delta = active_tree_->page_scale_delta();
-  gfx::PointF new_scale_anchor =
-      gfx::ScalePoint(anchor, 1.f / page_scale_delta);
+  float page_scale = active_tree_->current_page_scale_factor();
+  gfx::PointF previous_scale_anchor = gfx::ScalePoint(anchor, 1.f / page_scale);
+  active_tree_->SetPageScaleOnActiveTree(page_scale * magnify_delta);
+  page_scale = active_tree_->current_page_scale_factor();
+  gfx::PointF new_scale_anchor = gfx::ScalePoint(anchor, 1.f / page_scale);
   gfx::Vector2dF move = previous_scale_anchor - new_scale_anchor;
 
   previous_pinch_anchor_ = anchor;
 
-  move.Scale(1 / active_tree_->page_scale_factor());
   // If clamping the inner viewport scroll offset causes a change, it should
   // be accounted for from the intended move.
   move -= InnerViewportScrollLayer()->ClampScrollToMaxScrollOffset();
 
   // We manually manage the bubbling behaviour here as it is different to that
   // implemented in LayerTreeHostImpl::ScrollBy(). Specifically:
   // 1) we want to explicit limit the bubbling to the outer/inner viewports,
   // 2) we don't want the directional limitations on the unused parts that
   //    ScrollBy() implements, and
   // 3) pinching should not engage the top controls manager.
@@ skipping 46 matching lines @@
   }
 
   for (size_t i = 0; i < layer_impl->children().size(); ++i)
     CollectScrollDeltas(scroll_info, layer_impl->children()[i]);
 }
 
 scoped_ptr<ScrollAndScaleSet> LayerTreeHostImpl::ProcessScrollDeltas() {
   scoped_ptr<ScrollAndScaleSet> scroll_info(new ScrollAndScaleSet());
 
   CollectScrollDeltas(scroll_info.get(), active_tree_->root_layer());
-  scroll_info->page_scale_delta = active_tree_->page_scale_delta();
-  active_tree_->set_sent_page_scale_delta(scroll_info->page_scale_delta);
+  scroll_info->page_scale_delta =
+      active_tree_->page_scale_factor()->PullDeltaForMainThread();
   scroll_info->swap_promises.swap(swap_promises_for_main_thread_scroll_update_);
   scroll_info->top_controls_delta = active_tree()->top_controls_delta();
   active_tree_->set_sent_top_controls_delta(scroll_info->top_controls_delta);
 
   return scroll_info.Pass();
 }
 
 void LayerTreeHostImpl::SetFullRootLayerDamage() {
   SetViewportDamage(gfx::Rect(DrawViewportSize()));
 }
@@ skipping 21 matching lines @@
 
 void LayerTreeHostImpl::AnimatePageScale(base::TimeTicks monotonic_time) {
   if (!page_scale_animation_)
     return;
 
   gfx::ScrollOffset scroll_total = active_tree_->TotalScrollOffset();
 
   if (!page_scale_animation_->IsAnimationStarted())
     page_scale_animation_->StartAnimation(monotonic_time);
 
-  active_tree_->SetPageScaleDelta(
-      page_scale_animation_->PageScaleFactorAtTime(monotonic_time) /
-      active_tree_->page_scale_factor());
+  active_tree_->SetPageScaleOnActiveTree(
+      page_scale_animation_->PageScaleFactorAtTime(monotonic_time));
   gfx::ScrollOffset next_scroll = gfx::ScrollOffset(
       page_scale_animation_->ScrollOffsetAtTime(monotonic_time));
 
   ScrollViewportInnerFirst(next_scroll.DeltaFrom(scroll_total));
   SetNeedsRedraw();
 
   if (page_scale_animation_->IsAnimationCompleteAtTime(monotonic_time)) {
     page_scale_animation_ = nullptr;
     client_->SetNeedsCommitOnImplThread();
     client_->RenewTreePriority();
@@ skipping 11 matching lines @@
   if (top_controls_manager_->animation())
     SetNeedsAnimate();
 
   if (active_tree_->TotalScrollOffset().y() == 0.f)
     return;
 
   if (scroll.IsZero())
     return;
 
   ScrollViewportBy(gfx::ScaleVector2d(
-      scroll, 1.f / active_tree_->total_page_scale_factor()));
+      scroll, 1.f / active_tree_->current_page_scale_factor()));
   SetNeedsRedraw();
   client_->SetNeedsCommitOnImplThread();
   client_->RenewTreePriority();
 }
 
 void LayerTreeHostImpl::AnimateLayers(base::TimeTicks monotonic_time) {
   if (!settings_.accelerated_animation_enabled ||
       !needs_animate_layers() ||
       !active_tree_->root_layer())
     return;
@@ skipping 367 matching lines @@
 }
 
 void LayerTreeHostImpl::UnregisterPictureLayerImpl(PictureLayerImpl* layer) {
   std::vector<PictureLayerImpl*>::iterator it =
       std::find(picture_layers_.begin(), picture_layers_.end(), layer);
   DCHECK(it != picture_layers_.end());
   picture_layers_.erase(it);
 }
 
 }  // namespace cc