gyp: Properly set rtti flag

icu.gyp

 # Copyright (c) 2012 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.
 
 {
   'includes': [
     'icu.gypi',
   ],
   'variables': {
     'use_system_icu%': 0,
@@ skipping 198 matching lines @@
             ],
           },
           # Since ICU wants to internally use its own deprecated APIs, don't
           # complain about it.
           'cflags': [
             '-Wno-deprecated-declarations',
           ],
           'cflags_cc': [
             '-frtti',
           ],
+          'cflags_cc!': [
+            '-fno-rtti',
+          ],
           'xcode_settings': {
             'GCC_ENABLE_CPP_RTTI': 'YES',       # -frtti
           },
           'msvs_settings': {
             'VCCLCompilerTool': {
               'RuntimeTypeInfo': 'true',
             },
           },
           'conditions': [
             [ 'use_system_icu==1 and want_separate_host_toolset==1', {
@@ skipping 81 matching lines @@
           },
           'cflags': [
             # Since ICU wants to internally use its own deprecated APIs,
             # don't complain about it.
             '-Wno-deprecated-declarations',
             '-Wno-unused-function',
           ],
           'cflags_cc': [
             '-frtti',
           ],
+          'cflags_cc!': [
+            '-fno-rtti',
+          ],
           'xcode_settings': {
             'GCC_ENABLE_CPP_RTTI': 'YES',       # -frtti
           },
           'msvs_settings': {
             'VCCLCompilerTool': {
               'RuntimeTypeInfo': 'true',
             },
           },
           'all_dependent_settings': {
             'msvs_settings': {
@@ skipping 272 matching lines @@
           },
           'includes': [
             '../../build/shim_headers.gypi',
           ],
           'toolsets': ['target'],
         },
       ], # targets
     }],
   ], # conditions
 }