Fix cpplint errors in cc/(animation|input|layers|trees|test)/

cc/layers/layer_unittest.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/layers/layer.h"
 
 #include "cc/animation/keyframed_animation_curve.h"
 #include "cc/base/math_util.h"
 #include "cc/base/thread.h"
 #include "cc/layers/layer_impl.h"
@@ skipping 26 matching lines @@
     code_to_test;                                                         \
     Mock::VerifyAndClearExpectations(layer_tree_host_.get());           \
   } while (false)
 
 
 namespace cc {
 namespace {
 
 class MockLayerTreeHost : public LayerTreeHost {
  public:
-  MockLayerTreeHost(LayerTreeHostClient* client)
+  explicit MockLayerTreeHost(LayerTreeHostClient* client)
       : LayerTreeHost(client, LayerTreeSettings()) {
     Initialize(scoped_ptr<Thread>(NULL));
   }
 
   MOCK_METHOD0(SetNeedsCommit, void());
   MOCK_METHOD0(SetNeedsFullTreeSync, void());
 };
 
 class MockLayerPainter : public LayerPainter {
  public:
@@ skipping 944 matching lines @@
   layer->SetLayerTreeHost(layer_tree_host.get());
   AssertLayerTreeHostMatchesForSubtree(layer.get(), layer_tree_host.get());
 
   // Case 3: with a LayerTreeHost where accelerated animation is disabled, the
   // animation should be rejected.
   EXPECT_FALSE(AddTestAnimation(layer.get()));
 }
 
 }  // namespace
 }  // namespace cc