Backed out changeset a1d913968a8a (bug 1127289)

gfx/layers/client/TiledContentClient.cpp

@@ -1066,11 +1066,9 @@ ClientTiledLayerBuffer::UnlockTile(TileClient aTile)
   // We locked the back buffer, and flipped so we now need to unlock the front
   if (aTile.mFrontBuffer && aTile.mFrontBuffer->IsLocked()) {
     aTile.mFrontBuffer->Unlock();
-    aTile.mFrontBuffer->SyncWithObject(mCompositableClient->GetForwarder()->GetSyncObject());
   }
   if (aTile.mFrontBufferOnWhite && aTile.mFrontBufferOnWhite->IsLocked()) {
     aTile.mFrontBufferOnWhite->Unlock();
-    aTile.mFrontBufferOnWhite->SyncWithObject(mCompositableClient->GetForwarder()->GetSyncObject());
   }
   if (aTile.mBackBuffer && aTile.mBackBuffer->IsLocked()) {
     aTile.mBackBuffer->Unlock();
@@ -1290,6 +1288,8 @@ ClientTiledLayerBuffer::ValidateTile(TileClient aTile,
   tileRegion.SubOut(aDirtyRegion); // Has now been validated
 
   backBuffer->SetWaste(tileRegion.Area() * mResolution * mResolution);
+  backBuffer->Unlock();
+  backBuffer->SyncWithObject(mCompositableClient->GetForwarder()->GetSyncObject());
 
   if (createdTextureClient) {
     if (!mCompositableClient->AddTextureClient(backBuffer)) {