Remove bignum-dtoa.{cc, h} from gyp file.

tools/gyp/v8.gyp

 # Copyright 2009 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 264 matching lines @@
         '../../src/api.h',
         '../../src/apiutils.h',
         '../../src/arguments.h',
         '../../src/assembler.cc',
         '../../src/assembler.h',
         '../../src/ast.cc',
         '../../src/ast-inl.h',
         '../../src/ast.h',
         '../../src/bignum.cc',
         '../../src/bignum.h',
-        '../../src/bignum-dtoa.cc',
-        '../../src/bignum-dtoa.h',
         '../../src/bootstrapper.cc',
         '../../src/bootstrapper.h',
         '../../src/builtins.cc',
         '../../src/builtins.h',
         '../../src/bytecodes-irregexp.h',
         '../../src/cached-powers.cc',
         '../../src/cached-powers.h',
         '../../src/char-predicates-inl.h',
         '../../src/char-predicates.h',
         '../../src/checks.cc',
@@ skipping 449 matching lines @@
       ],
       'conditions': [
         ['OS=="win"', {
           # This could be gotten by not setting chromium_code, if that's OK.
           'defines': ['_CRT_SECURE_NO_WARNINGS'],
         }],
       ],
     },
   ],
 }