Fixed Mac gyp build. Switched to using Chrome hash_tables.h, changed...

build/common.gypi

 # Copyright (c) 2009 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 {
   'variables': {
     'antlrdir': 'third_party/antlr3',
     'breakpaddir': 'breakpad/src',
     'cb_service%': 'none',
     'fcolladadir': 'third_party/fcollada/files',
@@ skipping 16 matching lines @@
     'defines': [
       'GYP_BUILD',  # Needed to make a change in base/types.h conditional.
     ],
     # This needs to be in a target_conditions block in order to successfully
     # override the xcode_settings in ../../build/common.gypi.
     # Something to do with evaluation order.
     'target_conditions': [
       ['OS=="mac"', {
           'xcode_settings': {
             'MACOSX_DEPLOYMENT_TARGET': '10.4',
+            # TODO(maf): figure out proper fix for the following.
+            # There is only one place in plugin_mac.mm which attempts
+            # to use ObjC exception handling.
+            'GCC_ENABLE_CPP_EXCEPTIONS': 'YES',
           },
       }],
     ],
   },
   'conditions' : [
     ['OS == "win"',
       {
         'variables': {
           'renderer%': 'd3d9',
           'cgdir': 'third_party/cg/files/win',
@@ skipping 139 matching lines @@
       {
         'target_defaults': {
           'defines': [
             'CB_SERVICE_GL',
           ],
         },
       },
     ],
   ],
 }