Add compositor element id for scroll nodes in SPv2.

third_party/WebKit/Source/platform/graphics/compositing/PaintArtifactCompositorTest.cpp

 // Copyright 2016 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 "platform/graphics/compositing/PaintArtifactCompositor.h"
 
 #include "base/test/test_simple_task_runner.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "cc/layers/layer.h"
 #include "cc/test/fake_compositor_frame_sink.h"
@@ skipping 78 matching lines @@
         WTF::makeUnique<WebLayerTreeViewWithCompositorFrameSink>(settings);
     m_webLayerTreeView->setRootLayer(*m_paintArtifactCompositor->getWebLayer());
   }
 
   const cc::PropertyTrees& propertyTrees() {
     return *m_webLayerTreeView->layerTreeHost()
                 ->GetLayerTree()
                 ->property_trees();
   }
 
+  int elementIdToScrollNodeIndex(CompositorElementId elementId) {
+    return m_webLayerTreeView->layerTreeHost()
+        ->GetLayerTree()
+        ->property_trees()
+        ->element_id_to_scroll_node_index[elementId];
+  }
+
   const cc::TransformNode& transformNode(const cc::Layer* layer) {
     return *propertyTrees().transform_tree.Node(layer->transform_tree_index());
   }
 
   void update(const PaintArtifact& artifact) {
     m_paintArtifactCompositor->update(artifact, nullptr, false);
     m_webLayerTreeView->layerTreeHost()->LayoutAndUpdateLayers();
   }
 
   cc::Layer* rootLayer() { return m_paintArtifactCompositor->rootLayer(); }
@@ skipping 538 matching lines @@
   EXPECT_EQ(convertedEffect2.id, contentLayerAt(0)->effect_tree_index());
   EXPECT_EQ(convertedEffect1.id, contentLayerAt(1)->effect_tree_index());
   EXPECT_EQ(convertedEffect3.id, contentLayerAt(2)->effect_tree_index());
 }
 
 TEST_F(PaintArtifactCompositorTestWithPropertyTrees, OneScrollNode) {
   RefPtr<TransformPaintPropertyNode> scrollTranslation =
       TransformPaintPropertyNode::create(TransformPaintPropertyNode::root(),
                                          TransformationMatrix().translate(7, 9),
                                          FloatPoint3D());
+  CompositorElementId expectedCompositorElementId = CompositorElementId(2, 0);
   RefPtr<ScrollPaintPropertyNode> scroll = ScrollPaintPropertyNode::create(
       ScrollPaintPropertyNode::root(), scrollTranslation, IntSize(11, 13),
-      IntSize(27, 31), true, false, 0);
+      IntSize(27, 31), true, false, 0 /* mainThreadScrollingReasons */,
+      expectedCompositorElementId);
 
   TestPaintArtifact artifact;
   artifact
       .chunk(scrollTranslation, ClipPaintPropertyNode::root(),
              EffectPaintPropertyNode::root(), scroll)
       .rectDrawing(FloatRect(11, 13, 17, 19), Color::white);
   update(artifact.build());
 
   const cc::ScrollTree& scrollTree = propertyTrees().scroll_tree;
   // Node #0 reserved for null; #1 for root render surface.
   ASSERT_EQ(3u, scrollTree.size());
   const cc::ScrollNode& scrollNode = *scrollTree.Node(2);
   EXPECT_EQ(gfx::Size(11, 13), scrollNode.scroll_clip_layer_bounds);
   EXPECT_EQ(gfx::Size(27, 31), scrollNode.bounds);
   EXPECT_TRUE(scrollNode.user_scrollable_horizontal);
   EXPECT_FALSE(scrollNode.user_scrollable_vertical);
   EXPECT_EQ(1, scrollNode.parent_id);
+  EXPECT_EQ(expectedCompositorElementId, scrollNode.element_id);
+  EXPECT_EQ(scrollNode.id,
+            elementIdToScrollNodeIndex(expectedCompositorElementId));
 
   const cc::TransformTree& transformTree = propertyTrees().transform_tree;
   const cc::TransformNode& transformNode =
       *transformTree.Node(scrollNode.transform_id);
   EXPECT_TRUE(transformNode.local.IsIdentity());
 
   EXPECT_EQ(gfx::ScrollOffset(-7, -9),
             scrollTree.current_scroll_offset(contentLayerAt(0)->id()));
 
   EXPECT_EQ(MainThreadScrollingReason::kNotScrollingOnMain,
             scrollNode.main_thread_scrolling_reasons);
 }
 
 TEST_F(PaintArtifactCompositorTestWithPropertyTrees, NestedScrollNodes) {
   RefPtr<EffectPaintPropertyNode> effect =
       createOpacityOnlyEffect(EffectPaintPropertyNode::root(), 0.5);
 
+  CompositorElementId expectedCompositorElementIdA = CompositorElementId(2, 0);
+  CompositorElementId expectedCompositorElementIdB = CompositorElementId(3, 0);
   RefPtr<TransformPaintPropertyNode> scrollTranslationA =
       TransformPaintPropertyNode::create(
           TransformPaintPropertyNode::root(),
           TransformationMatrix().translate(11, 13), FloatPoint3D());
   RefPtr<ScrollPaintPropertyNode> scrollA = ScrollPaintPropertyNode::create(
       ScrollPaintPropertyNode::root(), scrollTranslationA, IntSize(2, 3),
       IntSize(5, 7), false, true,
-      MainThreadScrollingReason::kHasBackgroundAttachmentFixedObjects);
+      MainThreadScrollingReason::kHasBackgroundAttachmentFixedObjects,
+      expectedCompositorElementIdA);
   RefPtr<TransformPaintPropertyNode> scrollTranslationB =
       TransformPaintPropertyNode::create(
           scrollTranslationA, TransformationMatrix().translate(37, 41),
           FloatPoint3D());
   RefPtr<ScrollPaintPropertyNode> scrollB = ScrollPaintPropertyNode::create(
       scrollA, scrollTranslationB, IntSize(19, 23), IntSize(29, 31), true,
-      false, 0);
+      false, 0 /* mainThreadScrollingReasons */, expectedCompositorElementIdB);
   TestPaintArtifact artifact;
   artifact
       .chunk(scrollTranslationA, ClipPaintPropertyNode::root(), effect, scrollA)
       .rectDrawing(FloatRect(7, 11, 13, 17), Color::white);
   artifact
       .chunk(scrollTranslationB, ClipPaintPropertyNode::root(), effect, scrollB)
       .rectDrawing(FloatRect(1, 2, 3, 5), Color::white);
   update(artifact.build());
 
   const cc::ScrollTree& scrollTree = propertyTrees().scroll_tree;
   // Node #0 reserved for null; #1 for root render surface.
   ASSERT_EQ(4u, scrollTree.size());
   const cc::ScrollNode& scrollNodeA = *scrollTree.Node(2);
   EXPECT_EQ(gfx::Size(2, 3), scrollNodeA.scroll_clip_layer_bounds);
   EXPECT_EQ(gfx::Size(5, 7), scrollNodeA.bounds);
   EXPECT_FALSE(scrollNodeA.user_scrollable_horizontal);
   EXPECT_TRUE(scrollNodeA.user_scrollable_vertical);
   EXPECT_EQ(1, scrollNodeA.parent_id);
   const cc::ScrollNode& scrollNodeB = *scrollTree.Node(3);
   EXPECT_EQ(gfx::Size(19, 23), scrollNodeB.scroll_clip_layer_bounds);
   EXPECT_EQ(gfx::Size(29, 31), scrollNodeB.bounds);
   EXPECT_TRUE(scrollNodeB.user_scrollable_horizontal);
   EXPECT_FALSE(scrollNodeB.user_scrollable_vertical);
   EXPECT_EQ(scrollNodeA.id, scrollNodeB.parent_id);
+  EXPECT_EQ(expectedCompositorElementIdA, scrollNodeA.element_id);
+  EXPECT_EQ(scrollNodeA.id,
+            elementIdToScrollNodeIndex(expectedCompositorElementIdA));
+  EXPECT_EQ(expectedCompositorElementIdB, scrollNodeB.element_id);
+  EXPECT_EQ(scrollNodeB.id,
+            elementIdToScrollNodeIndex(expectedCompositorElementIdB));
 
   const cc::TransformTree& transformTree = propertyTrees().transform_tree;
   const cc::TransformNode& transformNodeA =
       *transformTree.Node(scrollNodeA.transform_id);
   EXPECT_TRUE(transformNodeA.local.IsIdentity());
   const cc::TransformNode& transformNodeB =
       *transformTree.Node(scrollNodeB.transform_id);
   EXPECT_TRUE(transformNodeB.local.IsIdentity());
 
   EXPECT_EQ(gfx::ScrollOffset(-11, -13),
@@ skipping 805 matching lines @@
   chunk3.properties.propertyTreeState = chunk1.properties.propertyTreeState;
   chunk3.bounds = FloatRect(0, 0, 50, 60);
   chunk3.knownToBeOpaque = true;
   pendingLayer.add(chunk3, nullptr);
 
   // Chunk 3 covers the entire layer, so now it's opaque.
   EXPECT_TRUE(pendingLayer.knownToBeOpaque);
 }
 
 }  // namespace blink