Unifies LayerTreeHost::SetNeedsUpdateLayers and SetNeedsAnimate

[2/2] Unifies LayerTreeHost::SetNeedsUpdateLayers and SetNeedsAnimate

They basically do the same thing except that SetNeedsAnimate makes the next
commit non-cancellable. However there is really no reason why SetNeedsAnimate
need to enforce a commit even if no tiles are updated and no layer properties
changed.

SetNeedsAnimate is thus merged into SetNeedsUpdateLayers. The proper use of
it is when there are potential layout/tile changes, we can use it to defer
calculation until the next frame. A commit will be scheduled but can be
cancelled if no updates are needed after calculation.

This part of the patch changes code behavior slightly.
SingleThreadProxy::SetNeedsUpdateLayers was originally implemented as
RenderWidget::ScheduleComposite but now it is RenderWidget::ScheduleAnimation.
ThreadProxy::SetNeedsAnimate was non-cancellable but is now cancellable.

[1/2] Cleanup RenderWidget::scheduleComposite/scheduleAnimation

scheduleComposite has been renamed to ScheduleComposite as it is no longer
a part of WebWidgetClient API.

scheduleAnimation has been renamed to ScheduleAnimation. The semantics is to
schedule a composite and also (potentially) animating WebWidget.

A new WebWidgetClient API scheduleUpdate has been added, to replace the old
scheduleAnimation. The semantics is to notify the embedder that something in
the WebWidget may change in 0 seconds. (i.e. it is allowed to be called
during a redraw, in such case another redraw will be scheduled after frame
delay.

This part of the patch should not change code behavior.

BUG=316929
R=danakj,jamesr,piman

Review URL: https://codereview.chromium.org/68893031

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@240008 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 12 insertions, 4 deletions

diff --git a/content/test/web_layer_tree_view_impl_for_testing.cc b/content/test/web_layer_tree_view_impl_for_testing.cc
index 1470e03..3a96c25 100644
--- a/content/test/web_layer_tree_view_impl_for_testing.cc
+++ b/content/test/web_layer_tree_view_impl_for_testing.cc
@@ -116,12 +116,19 @@ void WebLayerTreeViewImplForTesting::startPageScaleAnimation(
     float new_page_scale,
     double duration_sec) {}
 
+// Renamed. Staged for removal.
 void WebLayerTreeViewImplForTesting::setNeedsAnimate() {
-  layer_tree_host_->SetNeedsAnimate();
+  setNeedsUpdateLayers();
 }
 
+void WebLayerTreeViewImplForTesting::setNeedsUpdateLayers() {
+  layer_tree_host_->SetNeedsUpdateLayers();
+}
+
+// Unused. Staged for removal.
 bool WebLayerTreeViewImplForTesting::commitRequested() const {
-  return layer_tree_host_->CommitRequested();
+  NOTREACHED();
+  return false;
 }
 
 void WebLayerTreeViewImplForTesting::composite() {
diff --git a/content/test/web_layer_tree_view_impl_for_testing.h b/content/test/web_layer_tree_view_impl_for_testing.h
index 6fec0e3..47fa8e2 100644
--- a/content/test/web_layer_tree_view_impl_for_testing.h
+++ b/content/test/web_layer_tree_view_impl_for_testing.h
@@ -48,8 +48,9 @@ class WebLayerTreeViewImplForTesting
                                        bool use_anchor,
                                        float new_page_scale,
                                        double duration_sec);
-  virtual void setNeedsAnimate();
-  virtual bool commitRequested() const;
+  virtual void setNeedsAnimate(); // Renamed. Staged for removal.
+  virtual void setNeedsUpdateLayers();
+  virtual bool commitRequested() const; // Unused. Staged for removal.
   virtual void composite();
   virtual void didStopFlinging();
   virtual bool compositeAndReadback(void* pixels, const blink::WebRect& rect);