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

cc/layer_tree_host_impl_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/layer_tree_host_impl.h"
 
 #include <cmath>
 
 #include "base/bind.h"
 #include "base/command_line.h"
@@ skipping 2162 matching lines @@
     MOCK_METHOD0(getRequestableExtensionsCHROMIUM, WebKit::WebString());
     MOCK_METHOD1(enable, void(WebKit::WGC3Denum cap));
     MOCK_METHOD1(disable, void(WebKit::WGC3Denum cap));
     MOCK_METHOD4(scissor, void(WebKit::WGC3Dint x, WebKit::WGC3Dint y, WebKit::WGC3Dsizei width, WebKit::WGC3Dsizei height));
 };
 
 class MockContextHarness {
 private:
     MockContext* m_context;
 public:
-    MockContextHarness(MockContext* context)
+    explicit MockContextHarness(MockContext* context)
         : m_context(context)
     {
         // Catch "uninteresting" calls
         EXPECT_CALL(*m_context, useProgram(_))
             .Times(0);
 
         EXPECT_CALL(*m_context, drawElements(_, _, _, _))
             .Times(0);
 
         // These are not asserted
@@ skipping 2146 matching lines @@
     gfx::Rect noDamage = gfx::Rect(m_hostImpl->deviceViewportSize());
     drawFrameAndTestDamage(noDamage);
 }
 
 INSTANTIATE_TEST_CASE_P(LayerTreeHostImplTests,
                         LayerTreeHostImplTest,
                         ::testing::Values(false, true));
 
 }  // namespace
 }  // namespace cc