Temporarily don't redefine DISALLOW_IMPLICIT_CONSTRUCTORS in Blink.

Source/wtf/dtoa/utils.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 86 matching lines @@
 #define DISALLOW_COPY_AND_ASSIGN(TypeName)      \
 TypeName(const TypeName&);                    \
 void operator=(const TypeName&)
 
 // A macro to disallow all the implicit constructors, namely the
 // default constructor, copy constructor and operator= functions.
 //
 // This should be used in the private: declarations for a class
 // that wants to prevent anyone from instantiating it. This is
 // especially useful for classes containing only static methods.
+#ifndef DISALLOW_IMPLICIT_CONSTRUCTORS
 #define DISALLOW_IMPLICIT_CONSTRUCTORS(TypeName) \
-TypeName();                                    \
+TypeName() = delete;                             \
 DISALLOW_COPY_AND_ASSIGN(TypeName)
+#endif // DISALLOW_IMPLICIT_CONSTRUCTORS
 
 namespace WTF {
 
 namespace double_conversion {
 
     static const int kCharSize = sizeof(char);
 
     // Returns the maximum of the two parameters.
     template <typename T>
     static T Max(T a, T b) {
@@ skipping 178 matching lines @@
     template <class Dest, class Source>
     inline Dest BitCast(Source* source) {
         return BitCast<Dest>(reinterpret_cast<uintptr_t>(source));
     }
 
 }  // namespace double_conversion
 
 } // namespace WTF
 
 #endif  // DOUBLE_CONVERSION_UTILS_H_