Undo scroll snaps in to_parent when NeedsSourceToParentUpdate.

cc/trees/property_tree_unittest.cc

 // Copyright 2014 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/property_tree.h"
 
 #include "cc/input/main_thread_scrolling_reason.h"
 #include "cc/proto/property_tree.pb.h"
 #include "cc/test/geometry_test_utils.h"
 #include "cc/trees/clip_node.h"
@@ skipping 1053 matching lines @@
 class PropertyTreeTestNonIntegerTranslationTest : public PropertyTreeTest {
  protected:
   void StartTest() override {
     // This tests that when a node has non-integer translation, the information
     // is propagated to the subtree.
     PropertyTrees property_trees;
     TransformTree& tree = property_trees.transform_tree;
 
     int parent = tree.Insert(TransformNode(), 0);
     tree.SetTargetId(parent, parent);
+    tree.Node(parent)->source_node_id = 0;
     tree.Node(parent)->local.Translate(1.5f, 1.5f);
 
     int child = tree.Insert(TransformNode(), parent);
     tree.SetTargetId(child, parent);
     tree.Node(child)->local.Translate(1, 1);
+    tree.Node(child)->source_node_id = parent;
     tree.set_needs_update(true);
     SetupTransformTreeForTest(&tree);
     draw_property_utils::ComputeTransforms(&tree);
     EXPECT_FALSE(
         tree.Node(parent)->node_and_ancestors_have_only_integer_translation);
     EXPECT_FALSE(
         tree.Node(child)->node_and_ancestors_have_only_integer_translation);
 
     tree.Node(parent)->local.Translate(0.5f, 0.5f);
     tree.Node(child)->local.Translate(0.5f, 0.5f);
+    tree.Node(parent)->needs_local_transform_update = true;
+    tree.Node(child)->needs_local_transform_update = true;
     tree.set_needs_update(true);
     SetupTransformTreeForTest(&tree);
     draw_property_utils::ComputeTransforms(&tree);
     EXPECT_TRUE(
         tree.Node(parent)->node_and_ancestors_have_only_integer_translation);
     EXPECT_FALSE(
         tree.Node(child)->node_and_ancestors_have_only_integer_translation);
 
     tree.Node(child)->local.Translate(0.5f, 0.5f);
+    tree.Node(child)->needs_local_transform_update = true;
     tree.SetTargetId(child, child);
     tree.set_needs_update(true);
     SetupTransformTreeForTest(&tree);
     draw_property_utils::ComputeTransforms(&tree);
     EXPECT_TRUE(
         tree.Node(parent)->node_and_ancestors_have_only_integer_translation);
     EXPECT_TRUE(
         tree.Node(child)->node_and_ancestors_have_only_integer_translation);
   }
 };
 
 DIRECT_AND_SERIALIZED_PROPERTY_TREE_TEST_F(
     PropertyTreeTestNonIntegerTranslationTest);
 
 class PropertyTreeTestSingularTransformSnapTest : public PropertyTreeTest {
  protected:
   void StartTest() override {
     // This tests that to_target transform is not snapped when it has a singular
     // transform.
     PropertyTrees property_trees;
     property_trees.verify_transform_tree_calculations = true;
     TransformTree& tree = property_trees.transform_tree;
     EffectTree& effect_tree = property_trees.effect_tree;
 
     int parent = tree.Insert(TransformNode(), 0);
     int effect_parent = effect_tree.Insert(EffectNode(), 0);
     effect_tree.Node(effect_parent)->has_render_surface = true;
     tree.SetTargetId(parent, parent);
     tree.Node(parent)->scrolls = true;
+    tree.Node(parent)->source_node_id = 0;
 
     int child = tree.Insert(TransformNode(), parent);
     TransformNode* child_node = tree.Node(child);
     tree.SetTargetId(child, parent);
     child_node->scrolls = true;
     child_node->local.Scale3d(6.0f, 6.0f, 0.0f);
     child_node->local.Translate(1.3f, 1.3f);
+    child_node->source_node_id = parent;
     tree.set_needs_update(true);
 
     SetupTransformTreeForTest(&tree);
     draw_property_utils::ComputeTransforms(&tree);
     property_trees.ResetCachedData();
 
     gfx::Transform from_target;
     EXPECT_FALSE(tree.ToTarget(child, effect_parent).GetInverse(&from_target));
     // The following checks are to ensure that snapping is skipped because of
     // singular transform (and not because of other reasons which also cause
@@ skipping 11 matching lines @@
 
 DIRECT_AND_SERIALIZED_PROPERTY_TREE_TEST_F(
     PropertyTreeTestSingularTransformSnapTest);
 
 #undef DIRECT_AND_SERIALIZED_PROPERTY_TREE_TEST_F
 #undef SERIALIZED_PROPERTY_TREE_TEST_F
 #undef DIRECT_PROPERTY_TREE_TEST_F
 
 }  // namespace
 }  // namespace cc