Fix lint errors

src/liveedit.h

 // Copyright 2010 the V8 project authors. 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
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 47 matching lines @@
 // in a particular script. It gets called from compiler all the time, but
 // actually records any data only when liveedit operation is in process;
 // in any other time this class is very cheap.
 //
 // The primary interest of the Tracker is to record function scope structures
 // in order to analyze whether function code maybe safely patched (with new
 // code successfully reading existing data from function scopes). The Tracker
 // also collects compiled function codes.
 class LiveEditFunctionTracker {
  public:
-  LiveEditFunctionTracker(FunctionLiteral* fun);
+  explicit LiveEditFunctionTracker(FunctionLiteral* fun);
   ~LiveEditFunctionTracker();
   void RecordFunctionCode(Handle<Code> code);
   void RecordFunctionScope(Scope* scope);
 
   static bool IsActive();
 };
 
 } }  // namespace v8::internal
 
 #endif /* V*_LIVEEDIT_H_ */