Add missing (and remove superfluous) 'explicit' from constructors.

cc/test/fake_layer_tree_host_client.h

 // Copyright 2012 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.
 
 #ifndef CC_TEST_FAKE_LAYER_TREE_HOST_CLIENT_H_
 #define CC_TEST_FAKE_LAYER_TREE_HOST_CLIENT_H_
 
 #include "base/memory/scoped_ptr.h"
 #include "cc/font_atlas.h"
 #include "cc/input_handler.h"
 #include "cc/layer_tree_host.h"
 #include "cc/test/fake_output_surface.h"
 
 namespace cc {
 
 class FakeLayerImplTreeHostClient : public LayerTreeHostClient {
 public:
-    FakeLayerImplTreeHostClient(bool useSoftwareRendering = false, bool useDelegatingRenderer = false)
+    explicit FakeLayerImplTreeHostClient(bool useSoftwareRendering = false, bool useDelegatingRenderer = false)
         : m_useSoftwareRendering(useSoftwareRendering)
         , m_useDelegatingRenderer(useDelegatingRenderer)
     {
     }
 
     virtual void willBeginFrame() OVERRIDE { }
     virtual void didBeginFrame() OVERRIDE { }
     virtual void animate(double monotonicFrameBeginTime) OVERRIDE { }
     virtual void layout() OVERRIDE { }
     virtual void applyScrollAndScale(gfx::Vector2d scrollDelta, float pageScale) OVERRIDE { }
@@ skipping 12 matching lines @@
     virtual scoped_ptr<FontAtlas> createFontAtlas() OVERRIDE;
 
 private:
     bool m_useSoftwareRendering;
     bool m_useDelegatingRenderer;
 };
 
 }  // namespace cc
 
 #endif  // CC_TEST_FAKE_LAYER_TREE_HOST_CLIENT_H_