cc: Fix impl-side painting flashing due to missing tiles

cc: Fix impl-side painting flashing due to missing tiles

There was a bug where flashing could occur if a non-updated tiling was
used for activation.  As tiles only get created during
UpdateTilePriorities and null tiles are accepted for activation (under
the premise that there is nothing recorded there and tiles couldn't be
created), this could cause a premature activation and flashing content.

Fix this case by making sure that syncing a tiling always updates that
tiling if the tree is up to date and doesn't need update draw
properties.

Add checks to make sure that all tilings have been updated and the tree
itself is up to date when calling AreVisibleResourcesReady.

R=danakj@chromium.org
BUG=230540
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=198219

[enne (OOO), 2013-05-02 23:25:37]

https://codereview.chromium.org/14883003/diff/1/cc/layers/picture_layer_impl.cc
File cc/layers/picture_layer_impl.cc (right):

https://codereview.chromium.org/14883003/diff/1/cc/layers/picture_layer_impl....
cc/layers/picture_layer_impl.cc:381: const PictureLayerTiling* tiling,
This isn't actually needed.  I previously was trying to CreateTile as my check
to see if a null tile was ok, but abandoned that due to the fact that a null
tile can be both missing recorded region or live tiles rect.  The right check is
just to make sure the tiling has been updated.

However, making this const seemed pretty reasonable, so I left it.

[danakj, 2013-05-03 01:11:22]

LGTM

https://codereview.chromium.org/14883003/diff/4001/cc/resources/picture_layer...
File cc/resources/picture_layer_tiling.cc (right):

https://codereview.chromium.org/14883003/diff/4001/cc/resources/picture_layer...
cc/resources/picture_layer_tiling.cc:304: last_impl_frame_time_in_seconds_ =
current_frame_time_in_seconds;
Oh, word.

[commit-bot: I haz the power, 2013-05-03 01:11:28]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/enne@chromium.org/14883003/4001

[commit-bot: I haz the power, 2013-05-03 07:04:12]

Retried try job too often on linux_chromeos for step(s) ash_unittests
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=linux_chro...

[commit-bot: I haz the power, 2013-05-03 07:16:48]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/enne@chromium.org/14883003/4001

[commit-bot: I haz the power, 2013-05-03 07:16:51]

Failed to apply patch for cc/layers/picture_layer_impl.cc:
While running patch -p1 --forward --force --no-backup-if-mismatch;
  patching file cc/layers/picture_layer_impl.cc
  Hunk #1 FAILED at 524.
  Hunk #2 succeeded at 555 (offset -2 lines).
  Hunk #3 succeeded at 587 (offset -2 lines).
  1 out of 3 hunks FAILED -- saving rejects to file
cc/layers/picture_layer_impl.cc.rej

Patch:       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
24a83cb20d429bcac34b931df3ad32368278a5cd..f2fd744bf655edbca65a2aa2cc3f4e8c41829a8e
100644
--- a/cc/layers/picture_layer_impl.cc
+++ b/cc/layers/picture_layer_impl.cc
@@ -524,6 +524,13 @@ void PictureLayerImpl::SyncTiling(
   if (!DrawsContent() || tiling->contents_scale() < MinimumContentsScale())
     return;
   tilings_->Clone(tiling);
+
+  // If this tree needs update draw properties, then the tiling will
+  // get updated prior to drawing or activation.  If this tree does not
+  // need update draw properties, then its transforms are up to date and
+  // we can create tiles for this tiling immediately.
+  if (!layer_tree_impl()->needs_update_draw_properties())
+    UpdateTilePriorities();
 }
 
 void PictureLayerImpl::SetIsMask(bool is_mask) {
@@ -557,6 +564,7 @@ ResourceProvider::ResourceId
PictureLayerImpl::ContentsResourceId() const {
 
 bool PictureLayerImpl::AreVisibleResourcesReady() const {
   DCHECK(layer_tree_impl()->IsPendingTree());
+  DCHECK(!layer_tree_impl()->needs_update_draw_properties());
   DCHECK(ideal_contents_scale_);
 
   if (!tilings_->num_tilings())
@@ -588,6 +596,7 @@ bool PictureLayerImpl::AreVisibleResourcesReady() const {
   Region missing_region = rect;
   for (size_t i = 0; i < tilings_->num_tilings(); ++i) {
     PictureLayerTiling* tiling = tilings_->tiling_at(i);
+    DCHECK(tiling->has_ever_been_updated());
 
     if (tiling->contents_scale() < min_acceptable_scale)
       continue;

[commit-bot: I haz the power, 2013-05-03 16:28:34]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/enne@chromium.org/14883003/24001

[commit-bot: I haz the power, 2013-05-03 23:01:11]

Change committed as 198219