Use signaling NaN for holes in fixed double arrays.

tools/gyp/v8.gyp

 # Copyright 2012 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 1314 matching lines @@
         '../../src/base/division-by-constant.cc',
         '../../src/base/division-by-constant.h',
         '../../src/base/flags.h',
         '../../src/base/functional.cc',
         '../../src/base/functional.h',
         '../../src/base/iterator.h',
         '../../src/base/lazy-instance.h',
         '../../src/base/logging.cc',
         '../../src/base/logging.h',
         '../../src/base/macros.h',
+        '../../src/base/math.cc',
+        '../../src/base/math.h',
         '../../src/base/once.cc',
         '../../src/base/once.h',
         '../../src/base/platform/elapsed-timer.h',
         '../../src/base/platform/time.cc',
         '../../src/base/platform/time.h',
         '../../src/base/platform/condition-variable.cc',
         '../../src/base/platform/condition-variable.h',
         '../../src/base/platform/mutex.cc',
         '../../src/base/platform/mutex.h',
         '../../src/base/platform/platform.h',
@@ skipping 465 matching lines @@
         }],
         ['want_separate_host_toolset==1', {
           'toolsets': ['host'],
         }, {
           'toolsets': ['target'],
         }],
       ],
     },
   ],
 }