Missing explicit keyword in ctor of FooImpl.h

Source/web/WebFontImpl.h

 /*
  * Copyright (C) 2010 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 22 matching lines @@
 
 #include "platform/fonts/Font.h"
 #include "public/web/WebFont.h"
 
 namespace blink { class FontDescription; }
 
 namespace blink {
 
 class WebFontImpl FINAL : public WebFont {
 public:
-    WebFontImpl(const blink::FontDescription&);
+    explicit WebFontImpl(const blink::FontDescription&);
 
     virtual WebFontDescription fontDescription() const OVERRIDE;
 
     virtual int ascent() const OVERRIDE;
     virtual int descent() const OVERRIDE;
     virtual int height() const OVERRIDE;
     virtual int lineSpacing() const OVERRIDE;
     virtual float xHeight() const OVERRIDE;
 
     virtual void drawText(WebCanvas*, const WebTextRun&, const WebFloatPoint& leftBaseline, WebColor,
         const WebRect& clip, bool canvasIsOpaque, int from = 0, int to = -1) const OVERRIDE;
     virtual int calculateWidth(const WebTextRun&) const OVERRIDE;
     virtual int offsetForPosition(const WebTextRun&, float position) const OVERRIDE;
     virtual WebFloatRect selectionRectForText(const WebTextRun&, const WebFloatPoint& leftBaseline,
         int height, int from = 0, int to = -1) const OVERRIDE;
 
 private:
     blink::Font m_font;
 };
 
 } // namespace blink
 
 #endif