cc: Use visible_rect_for_tile_priority_ where approriate

cc/layers/picture_layer_impl.cc

Index: cc/layers/picture_layer_impl.cc
diff --git a/cc/layers/picture_layer_impl.cc b/cc/layers/picture_layer_impl.cc
index eaccbbf46ba873ebf196ad8f02c92c0a4a47db51..7802f3c369c9c2b44bc27cd0bbc3a08bbe02f470 100644
--- a/cc/layers/picture_layer_impl.cc
+++ b/cc/layers/picture_layer_impl.cc
@@ -449,7 +449,9 @@ void PictureLayerImpl::UpdateTiles(
 
   DoPostCommitInitializationIfNeeded();
 
-  visible_rect_for_tile_priority_ = visible_content_rect();
+  if (!layer_tree_impl()->resourceless_software_draw()) {

[danakj, 2014/09/30 21:06:37]

can we pass this to UpdateTiles instead of making it call back to LayerTreeImpl,
where it just came from?

[boliu, 2014/09/30 23:52:02]

This is *not* done yet in PS3. Looks like going to involve a bit of churn, so
gonna do it on top of PS3 and see how this goes.

+    visible_rect_for_tile_priority_ = visible_content_rect();
+  }
   viewport_rect_for_tile_priority_ =

[danakj, 2014/09/30 20:38:37]

the assign before this is completely overridden here, do you mean if else, or
what's going on here?

[danakj, 2014/09/30 20:39:03]

oh visible/viewport, reading how does it work?

       layer_tree_impl()->ViewportRectForTilePriority();
   screen_space_transform_for_tile_priority_ = screen_space_transform();
@@ -806,7 +808,7 @@ void PictureLayerImpl::MarkVisibleResourcesAsRequired() const {
   // higher res on the active tree to a lower res on the pending tree.
 
   // First, early out for layers with no visible content.
-  if (visible_content_rect().IsEmpty())
+  if (visible_rect_for_tile_priority_.IsEmpty())
     return;
 
   // Only mark tiles inside the viewport for tile priority as required for
@@ -814,7 +816,7 @@ void PictureLayerImpl::MarkVisibleResourcesAsRequired() const {
   // can be independently overridden by embedders like Android WebView with
   // SetExternalDrawConstraints.
   gfx::Rect rect = GetViewportForTilePriorityInContentSpace();
-  rect.Intersect(visible_content_rect());
+  rect.Intersect(visible_rect_for_tile_priority_);
 
   float min_acceptable_scale =
       std::min(raster_contents_scale_, ideal_contents_scale_);
@@ -1492,7 +1494,7 @@ bool PictureLayerImpl::AllTilesRequiredForActivationAreReadyToDraw() const {
   if (!tilings_)
     return true;
 
-  if (visible_content_rect().IsEmpty())
+  if (visible_rect_for_tile_priority_.IsEmpty())
     return true;
 
   for (size_t i = 0; i < tilings_->num_tilings(); ++i) {
@@ -1501,7 +1503,7 @@ bool PictureLayerImpl::AllTilesRequiredForActivationAreReadyToDraw() const {
         tiling->resolution() != LOW_RESOLUTION)
       continue;
 
-    gfx::Rect rect(visible_content_rect());
+    gfx::Rect rect(visible_rect_for_tile_priority_);

[danakj, 2014/09/30 21:05:53]

Why isn't this using GetViewportForTilePriorityInContentSpace() intersect this
rect, like when we mark required? can you explain either way the background for
this decision? Maybe this should be a comment if it should be different from
marking.

[boliu, 2014/09/30 22:37:48]

omg this is an existing bug! It should be
GetViewportForTilePriorityInContentSpace afaict. I missed this method when in
this change, when I changed the activation rect in
https://codereview.chromium.org/475233002/

Looks like no one has noticed yet...

     for (PictureLayerTiling::CoverageIterator iter(tiling, 1.f, rect); iter;
          ++iter) {
       const Tile* tile = *iter;