Update property trees' bounds delta before updating viewport container sizes.

cc/trees/layer_tree_host_impl.cc

 // Copyright 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/trees/layer_tree_host_impl.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <algorithm>
@@ skipping 1968 matching lines @@
     if (pending_tree_->root_layer())
       pending_tree_->property_trees()->ResetAllChangeTracking(
           PropertyTrees::ResetFlags::ALL_TREES);
 
     // Now that we've synced everything from the pending tree to the active
     // tree, rename the pending tree the recycle tree so we can reuse it on the
     // next sync.
     DCHECK(!recycle_tree_);
     pending_tree_.swap(recycle_tree_);
 
-    UpdateViewportContainerSizes();
-
     // If we commit to the active tree directly, this is already done during
     // commit.
     ActivateAnimations();
   } else {
     active_tree_->ProcessUIResourceRequestQueue();
   }
 
   // bounds_delta isn't a pushed property, so the newly-pushed property tree
-  // won't already account for current bounds_delta values.
+  // won't already account for current bounds_delta values. This needs to
+  // happen before calling UpdateViewportContainerSizes().
   active_tree_->UpdatePropertyTreesForBoundsDelta();
+  UpdateViewportContainerSizes();
+
   active_tree_->DidBecomeActive();
   client_->RenewTreePriority();
   // If we have any picture layers, then by activating we also modified tile
   // priorities.
   if (!active_tree_->picture_layers().empty())
     DidModifyTilePriorities();
 
   client_->OnCanDrawStateChanged(CanDraw());
   client_->DidActivateSyncTree();
   if (!tree_activation_callback_.is_null())
@@ skipping 1911 matching lines @@
   return task_runner_provider_->HasImplThread();
 }
 
 bool LayerTreeHostImpl::CommitToActiveTree() const {
   // In single threaded mode we skip the pending tree and commit directly to the
   // active tree.
   return !task_runner_provider_->HasImplThread();
 }
 
 }  // namespace cc