cc: Make 1/4th default low res scale.

cc/layers/picture_layer_impl_unittest.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/layers/picture_layer_impl.h"
 
 #include <utility>
 
 #include "cc/debug/test_web_graphics_context_3d.h"
 #include "cc/layers/append_quads_data.h"
@@ skipping 724 matching lines @@
 
   // Stop animating, low res gets created.
   animating_transform = false;
   SetContentsScaleOnBothLayers(
       contents_scale, device_scale, page_scale, animating_transform);
   EXPECT_BOTH_EQ(HighResTiling()->contents_scale(), 1.f);
   EXPECT_BOTH_EQ(LowResTiling()->contents_scale(), low_res_factor);
   EXPECT_BOTH_EQ(num_tilings(), 2u);
 
   // Page scale animation, new high res, but not new low res because animating.
-  contents_scale = 4.f;
-  page_scale = 4.f;
+  contents_scale = 2.f;
+  page_scale = 2.f;
   animating_transform = true;
   SetContentsScaleOnBothLayers(
       contents_scale, device_scale, page_scale, animating_transform);
-  EXPECT_BOTH_EQ(HighResTiling()->contents_scale(), 4.f);
+  EXPECT_BOTH_EQ(HighResTiling()->contents_scale(), 2.f);
   EXPECT_BOTH_EQ(LowResTiling()->contents_scale(), low_res_factor);
   EXPECT_BOTH_EQ(num_tilings(), 3u);
 
   // Stop animating, new low res gets created for final page scale.
   animating_transform = false;
   SetContentsScaleOnBothLayers(
       contents_scale, device_scale, page_scale, animating_transform);
-  EXPECT_BOTH_EQ(HighResTiling()->contents_scale(), 4.f);
-  EXPECT_BOTH_EQ(LowResTiling()->contents_scale(), 4.f * low_res_factor);
+  EXPECT_BOTH_EQ(HighResTiling()->contents_scale(), 2.f);
+  EXPECT_BOTH_EQ(LowResTiling()->contents_scale(), 2.f * low_res_factor);
   EXPECT_BOTH_EQ(num_tilings(), 4u);
 }
 
 TEST_F(PictureLayerImplTest, DontAddLowResForSmallLayers) {
   gfx::Size tile_size(host_impl_.settings().default_tile_size);
   SetupDefaultTrees(tile_size);
 
   float low_res_factor = host_impl_.settings().low_res_contents_scale_factor;
   float device_scale = 1.f;
   float page_scale = 1.f;
@@ skipping 389 matching lines @@
       TestContextProvider::Create(), NULL));
 
   // These will crash PictureLayerImpl if this is not true.
   ASSERT_TRUE(host_impl_.pending_tree()->needs_update_draw_properties());
   ASSERT_TRUE(host_impl_.active_tree()->needs_update_draw_properties());
   host_impl_.active_tree()->UpdateDrawProperties();
 }
 
 }  // namespace
 }  // namespace cc