Update Viewport Clip in LayerTreeHostImpl::SetViewportSize

If LayerTreeHostImpl::SetViewportSize updates viewport and
we do hit testing before the activation of the pending tree,
the active tree uses the old properties. So, its necessary
to update clip tree as soon as viewport size changes.
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel

Review URL: https://codereview.chromium.org/1318113003

Cr-Commit-Position: refs/heads/master@{#346049}

1 files changed, 16 insertions, 0 deletions

diff --git a/cc/trees/property_tree.cc b/cc/trees/property_tree.cc
index df3e3cc..d65a142 100644
--- a/cc/trees/property_tree.cc
+++ b/cc/trees/property_tree.cc
@@ -591,6 +591,22 @@ void TransformTree::UpdateNodeAndAncestorsHaveIntegerTranslations(
         parent_node->data.node_and_ancestors_have_only_integer_translation;
 }
 
+void ClipTree::SetViewportClip(gfx::RectF viewport_rect) {
+  if (size() < 2)
+    return;
+  ClipNode* node = Node(1);
+  if (viewport_rect == node->data.clip)
+    return;
+  node->data.clip = viewport_rect;
+  set_needs_update(true);
+}
+
+gfx::RectF ClipTree::ViewportClip() {
+  const unsigned long min_size = 1;
+  DCHECK_GT(size(), min_size);
+  return Node(1)->data.clip;
+}
+
 PropertyTrees::PropertyTrees() : needs_rebuild(true), sequence_number(0) {
 }