Introduce a v8::Platform class that bundles embedder callbacks

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 263 matching lines @@
         '../../src/data-flow.h',
         '../../src/date.cc',
         '../../src/date.h',
         '../../src/dateparser-inl.h',
         '../../src/dateparser.cc',
         '../../src/dateparser.h',
         '../../src/debug-agent.cc',
         '../../src/debug-agent.h',
         '../../src/debug.cc',
         '../../src/debug.h',
+        '../../src/default-platform.cc',
+        '../../src/default-platform.h',
         '../../src/deoptimizer.cc',
         '../../src/deoptimizer.h',
         '../../src/disasm.h',
         '../../src/disassembler.cc',
         '../../src/disassembler.h',
         '../../src/diy-fp.cc',
         '../../src/diy-fp.h',
         '../../src/double.h',
         '../../src/dtoa.cc',
         '../../src/dtoa.h',
@@ skipping 590 matching lines @@
           'sources!': [
             '../../src/i18n.cc',
             '../../src/i18n.h',
           ],
         }],
         ['OS=="win" and v8_enable_i18n_support==1', {
           'dependencies': [
             '<(icu_gyp_path):icudata',
           ],
         }],
+        ['v8_use_default_platform==0', {
+          'sources!': [
+            '../../src/default-platform.cc',
+            '../../src/default-platform.h',
+          ],
+        }],
       ],
     },
     {
       'target_name': 'js2c',
       'type': 'none',
       'conditions': [
         ['want_separate_host_toolset==1', {
           'toolsets': ['host'],
         }, {
           'toolsets': ['target'],
@@ skipping 159 matching lines @@
         }],
         ['v8_compress_startup_data=="bz2"', {
           'libraries': [
             '-lbz2',
           ]
         }],
       ],
     },
   ],
 }