Don't set sent_top_controls_delta when root layer doesn't exist.

cc/trees/layer_tree_host_impl_unittest.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 <cmath>
 
 #include "base/bind.h"
 #include "base/command_line.h"
@@ skipping 2232 matching lines @@
         clip_size_(layer_size_) {
     settings_.calculate_top_controls_position = true;
     settings_.top_controls_height = 50;
 
     viewport_size_ =
         gfx::Size(clip_size_.width(),
                   clip_size_.height() + settings_.top_controls_height);
   }
 
   void SetupTopControlsAndScrollLayer() {
-    CreateHostImpl(settings_, CreateOutputSurface());
-
     scoped_ptr<LayerImpl> root =
         LayerImpl::Create(host_impl_->active_tree(), 1);
     scoped_ptr<LayerImpl> root_clip =
         LayerImpl::Create(host_impl_->active_tree(), 2);
     root_clip->SetBounds(clip_size_);
     root->SetScrollClipLayer(root_clip->id());
     root->SetBounds(layer_size_);
     root->SetContentBounds(layer_size_);
     root->SetPosition(gfx::PointF());
     root->SetDrawsContent(false);
     root->SetIsContainerForFixedPositionLayers(true);
     int inner_viewport_scroll_layer_id = root->id();
     int page_scale_layer_id = root_clip->id();
     root_clip->AddChild(root.Pass());
     host_impl_->active_tree()->SetRootLayer(root_clip.Pass());
     host_impl_->active_tree()->SetViewportLayersFromIds(
         page_scale_layer_id, inner_viewport_scroll_layer_id, Layer::INVALID_ID);
     // Set a viewport size that is large enough to contain both the top controls
     // and some content.
     host_impl_->SetViewportSize(viewport_size_);
     host_impl_->SetTopControlsLayoutHeight(
         settings_.top_controls_height);
-    LayerImpl* root_clip_ptr = host_impl_->active_tree()->root_layer();
-    EXPECT_EQ(clip_size_, root_clip_ptr->bounds());
 
     host_impl_->CreatePendingTree();
     root =
         LayerImpl::Create(host_impl_->sync_tree(), 1);
     root_clip =
         LayerImpl::Create(host_impl_->sync_tree(), 2);
     root_clip->SetBounds(clip_size_);
     root->SetScrollClipLayer(root_clip->id());
     root->SetBounds(layer_size_);
     root->SetContentBounds(layer_size_);
     root->SetPosition(gfx::PointF());
     root->SetDrawsContent(false);
     root->SetIsContainerForFixedPositionLayers(true);
     inner_viewport_scroll_layer_id = root->id();
     page_scale_layer_id = root_clip->id();
     root_clip->AddChild(root.Pass());
     host_impl_->sync_tree()->SetRootLayer(root_clip.Pass());
     host_impl_->sync_tree()->SetViewportLayersFromIds(
         page_scale_layer_id, inner_viewport_scroll_layer_id, Layer::INVALID_ID);
     // Set a viewport size that is large enough to contain both the top controls
     // and some content.
     host_impl_->SetViewportSize(viewport_size_);
     host_impl_->sync_tree()->set_top_controls_layout_height(
         settings_.top_controls_height);
-    root_clip_ptr = host_impl_->sync_tree()->root_layer();
-    EXPECT_EQ(clip_size_, root_clip_ptr->bounds());
   }
 
  protected:
   gfx::Size layer_size_;
   gfx::Size clip_size_;
   gfx::Size viewport_size_;
 
   LayerTreeSettings settings_;
 };  // class LayerTreeHostImplTopControlsTest
 
+TEST_F(LayerTreeHostImplTopControlsTest,
+       TopControlsDeltaOnlySentWithRootLayer) {
+  CreateHostImpl(settings_, CreateOutputSurface());
+
+  host_impl_->active_tree()->set_top_controls_delta(-20.f);
+
+  // Because LTH::ApplyScrollAndScale doesn't know what to do with a scroll
+  // delta packet when the root layer doesn't exist yet, make sure not to set
+  // sent_top_controls_delta either to avoid the delta getting clobbered on the
+  // next commit.
+  scoped_ptr<ScrollAndScaleSet> scroll_info = host_impl_->ProcessScrollDeltas();
+  EXPECT_EQ(scroll_info->top_controls_delta, 0.f);
+  EXPECT_EQ(host_impl_->active_tree()->sent_top_controls_delta(), 0.f);
+
+  SetupTopControlsAndScrollLayer();
+
+  // After the root layer exists, it should be set normally.
+  scroll_info = host_impl_->ProcessScrollDeltas();
+  EXPECT_EQ(scroll_info->top_controls_delta, -20.f);
+  EXPECT_EQ(host_impl_->active_tree()->sent_top_controls_delta(), -20.f);
+}
+
 TEST_F(LayerTreeHostImplTopControlsTest, ScrollTopControlsByFractionalAmount) {
+  CreateHostImpl(settings_, CreateOutputSurface());
   SetupTopControlsAndScrollLayer();
   DrawFrame();
 
   EXPECT_EQ(InputHandler::ScrollStarted,
             host_impl_->ScrollBegin(gfx::Point(), InputHandler::Gesture));
 
   // Make the test scroll delta a fractional amount, to verify that the
   // fixed container size delta is (1) non-zero, and (2) fractional, and
   // (3) matches the movement of the top controls.
   gfx::Vector2dF top_controls_scroll_delta(0.f, 5.25f);
   host_impl_->top_controls_manager()->ScrollBegin();
   host_impl_->top_controls_manager()->ScrollBy(top_controls_scroll_delta);
   host_impl_->top_controls_manager()->ScrollEnd();
 
   LayerImpl* inner_viewport_scroll_layer =
       host_impl_->active_tree()->InnerViewportScrollLayer();
   DCHECK(inner_viewport_scroll_layer);
   host_impl_->ScrollEnd();
   EXPECT_EQ(top_controls_scroll_delta,
             inner_viewport_scroll_layer->FixedContainerSizeDelta());
 }
 
 TEST_F(LayerTreeHostImplTopControlsTest, ScrollTopControlsWithPageScale) {
+  CreateHostImpl(settings_, CreateOutputSurface());
   SetupTopControlsAndScrollLayer();
   DrawFrame();
 
   EXPECT_EQ(InputHandler::ScrollStarted,
             host_impl_->ScrollBegin(gfx::Point(), InputHandler::Gesture));
 
   float page_scale = 1.5f;
   host_impl_->active_tree()->SetPageScaleFactorAndLimits(page_scale, 1.f, 2.f);
 
   gfx::Vector2dF top_controls_scroll_delta(0.f, 5.f);
@@ skipping 13 matching lines @@
   double tolerance = 0.0001;
   EXPECT_LT(
       (expected_container_size_delta -
        inner_viewport_scroll_layer->FixedContainerSizeDelta()).LengthSquared(),
       tolerance);
 }
 
 // Ensure setting the top controls position explicitly using the setters on the
 // TreeImpl correctly affects the top controls manager and viewport bounds.
 TEST_F(LayerTreeHostImplTopControlsTest, PositionTopControlsExplicitly) {
+  CreateHostImpl(settings_, CreateOutputSurface());
   SetupTopControlsAndScrollLayer();
   DrawFrame();
 
   host_impl_->active_tree()->set_top_controls_delta(0.f);
   host_impl_->active_tree()->set_top_controls_content_offset(30.f);
   EXPECT_EQ(30.f, host_impl_->top_controls_manager()->ContentTopOffset());
   EXPECT_EQ(-20.f, host_impl_->top_controls_manager()->ControlsTopOffset());
 
   host_impl_->active_tree()->set_top_controls_delta(-30.f);
   EXPECT_EQ(0.f, host_impl_->top_controls_manager()->ContentTopOffset());
   EXPECT_EQ(-50.f, host_impl_->top_controls_manager()->ControlsTopOffset());
 
   host_impl_->DidChangeTopControlsPosition();
 
   // Now that top controls have moved, expect the clip to resize.
   LayerImpl* root_clip_ptr = host_impl_->active_tree()->root_layer();
   EXPECT_EQ(viewport_size_, root_clip_ptr->bounds());
 }
 
 // Test that the top_controls delta and sent delta are appropriately
 // applied on sync tree activation. The total top controls offset shouldn't
 // change after the activation.
 TEST_F(LayerTreeHostImplTopControlsTest, ApplyDeltaOnTreeActivation) {
+  CreateHostImpl(settings_, CreateOutputSurface());
   SetupTopControlsAndScrollLayer();
   DrawFrame();
 
   host_impl_->sync_tree()->set_top_controls_content_offset(15.f);
 
   host_impl_->active_tree()->set_top_controls_content_offset(20.f);
   host_impl_->active_tree()->set_top_controls_delta(-20.f);
   host_impl_->active_tree()->set_sent_top_controls_delta(-5.f);
 
   host_impl_->DidChangeTopControlsPosition();
@@ skipping 14 matching lines @@
   EXPECT_EQ(15.f, host_impl_->active_tree()->top_controls_content_offset());
   EXPECT_EQ(0.f,
       host_impl_->active_tree()->total_top_controls_content_offset());
 }
 
 // Test that changing the top controls layout height is correctly applied to
 // the inner viewport container bounds. That is, the top controls layout
 // height is the amount that the inner viewport container was shrunk outside
 // the compositor to accommodate the top controls.
 TEST_F(LayerTreeHostImplTopControlsTest, TopControlsLayoutHeightChanged) {
+  CreateHostImpl(settings_, CreateOutputSurface());
   SetupTopControlsAndScrollLayer();
   DrawFrame();
 
   host_impl_->sync_tree()->set_top_controls_content_offset(15.f);
   host_impl_->sync_tree()->set_top_controls_layout_height(15.f);
 
   host_impl_->active_tree()->set_top_controls_content_offset(20.f);
   host_impl_->active_tree()->set_top_controls_delta(-20.f);
   host_impl_->active_tree()->set_sent_top_controls_delta(-5.f);
 
@@ skipping 21 matching lines @@
   host_impl_->DidChangeTopControlsPosition();
 
   EXPECT_EQ(15.f, host_impl_->top_controls_manager()->ContentTopOffset());
   EXPECT_VECTOR_EQ(gfx::Vector2dF(0.f, 0.f), root_clip_ptr->bounds_delta());
   EXPECT_EQ(gfx::Size(viewport_size_.width(), viewport_size_.height()-15.f),
             root_clip_ptr->bounds());
 }
 
 TEST_F(LayerTreeHostImplTopControlsTest,
        ScrollNonScrollableRootWithTopControls) {
+  CreateHostImpl(settings_, CreateOutputSurface());
   SetupTopControlsAndScrollLayer();
   DrawFrame();
 
   EXPECT_EQ(InputHandler::ScrollStarted,
             host_impl_->ScrollBegin(gfx::Point(), InputHandler::Gesture));
 
   host_impl_->top_controls_manager()->ScrollBegin();
   host_impl_->top_controls_manager()->ScrollBy(gfx::Vector2dF(0.f, 50.f));
   host_impl_->top_controls_manager()->ScrollEnd();
   EXPECT_EQ(0.f, host_impl_->top_controls_manager()->ContentTopOffset());
@@ skipping 4791 matching lines @@
   // surface.
   EXPECT_EQ(0, num_lost_surfaces_);
   host_impl_->DidLoseOutputSurface();
   EXPECT_EQ(1, num_lost_surfaces_);
   host_impl_->DidLoseOutputSurface();
   EXPECT_LE(1, num_lost_surfaces_);
 }
 
 }  // namespace
 }  // namespace cc