Fixing crash in PictureLayerImpl::MarkVisibleResourcesAsRequired when low-res tiles are disabled

cc/test/fake_picture_layer_impl.cc

 // Copyright 2013 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/test/fake_picture_layer_impl.h"
 
 #include <vector>
 #include "cc/resources/tile.h"
 #include "cc/trees/layer_tree_impl.h"
 
@@ skipping 118 matching lines @@
     for (size_t mode_idx = 0; mode_idx < NUM_RASTER_MODES; ++mode_idx)
       state.tile_versions[mode_idx].SetSolidColorForTesting(true);
     DCHECK(tile->IsReadyToDraw());
   }
 }
 
 void FakePictureLayerImpl::CreateDefaultTilingsAndTiles() {
   layer_tree_impl()->UpdateDrawProperties();
 
   if (CanHaveTilings()) {
-    DCHECK_EQ(tilings()->num_tilings(), 2u);
+    DCHECK_EQ(
+        tilings()->num_tilings(),
+        layer_tree_impl()->settings().create_low_res_tiling ? 2u : 1u);
     DCHECK_EQ(tilings()->tiling_at(0)->resolution(), HIGH_RESOLUTION);
-    DCHECK_EQ(tilings()->tiling_at(1)->resolution(), LOW_RESOLUTION);
     HighResTiling()->CreateAllTilesForTesting();
-    LowResTiling()->CreateAllTilesForTesting();
+    if (layer_tree_impl()->settings().create_low_res_tiling) {
+      DCHECK_EQ(tilings()->tiling_at(1)->resolution(), LOW_RESOLUTION);
+      LowResTiling()->CreateAllTilesForTesting();
+    }
   } else {
     DCHECK_EQ(tilings()->num_tilings(), 0u);
   }
 }
 
 }  // namespace cc