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

Review URL: http://codereview.chromium.org/4673002

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5788 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

tools/gyp/v8.gyp

@@ -282,8 +282,6 @@
         '../../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',