cc: Block commit on activate by setting a flag on LayerTreeHost.

Currently the ThreadProxy recursively asks all layers in the tree if
they should block the commit. This is problematic as when you remove
a layer from a the tree, it may want to block the commit to get back
resources from its active-tree impl-layer.

Instead, have layers call SetNextCommitWaitsForActivation() when they
want the next commit to block on activate. This way we only block
commits that matter, not every commit when there's a texture layer
present. And we can allow a layer to block the commit when it is
leaving the tree.

Tests:
TextureLayerNoMailboxIsActivatedDuringCommit
TextureLayerMailboxIsActivatedDuringCommit
DelegatedFrameIsActivatedDuringCommit

R=enne, piman
BUG=277953

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=220418

Review URL: https://chromiumcodereview.appspot.com/23530003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@220515 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 4 insertions, 2 deletions

diff --git a/cc/layers/tiled_layer.cc b/cc/layers/tiled_layer.cc
index 556b8231..2d812e8 100644
--- a/cc/layers/tiled_layer.cc
+++ b/cc/layers/tiled_layer.cc
@@ -235,8 +235,6 @@ void TiledLayer::PushPropertiesTo(LayerImpl* layer) {
   needs_push_properties_ = true;
 }
 
-bool TiledLayer::BlocksPendingCommit() const { return true; }
-
 PrioritizedResourceManager* TiledLayer::ResourceManager() {
   if (!layer_tree_host())
     return NULL;
@@ -731,6 +729,10 @@ bool TiledLayer::Update(ResourceUpdateQueue* queue,
                         const OcclusionTracker* occlusion) {
   DCHECK(!skips_draw_ && !failed_update_);  // Did ResetUpdateState get skipped?
 
+  // Tiled layer always causes commits to wait for activation, as it does
+  // not support pending trees.
+  SetNextCommitWaitsForActivation();
+
   bool updated = false;
 
   {