Match GN and GYP compilation warning flags

build_gyp/standalone.gypi

 # Copyright 2014 PDFium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # Definitions to be used when building stand-alone PDFium binaries.
 
 {
   'variables': {
     'component%': 'static_library',
     'chromium_code%': 0,
@@ skipping 184 matching lines @@
       'V8_DEPRECATION_WARNINGS',
     ],
     'msvs_cygwin_dirs': ['<(DEPTH)/v8/third_party/cygwin'],
     'msvs_configuration_attributes': {
       'OutputDirectory': '<(DEPTH)\\build\\$(ConfigurationName)',
       'IntermediateDirectory': '$(OutDir)\\obj\\$(ProjectName)',
       'CharacterSet': '1',
     },
     'msvs_disabled_warnings': [
       # ####
-      # This section is PDFium specific.

[Lei Zhang, 2016/05/27 23:49:20]

Can you leave this section here? We still refer to it on line 292.

[Wei Li, 2016/05/28 00:11:59]

sure.

-      # ####
-
-      # C4800: forcing value to bool 'true' or 'false' (performance warning)

[Lei Zhang, 2016/05/27 23:49:20]

Just mention this section is currently empty.

[Wei Li, 2016/05/28 00:11:59]

Done.

-      4800,
-
-      # ####
       # This section should match Chromium's build/common.gypi.
       # ####
 
       # C4091: 'typedef ': ignored on left of 'X' when no variable is
       #                    declared.
       # This happens in a number of Windows headers. Dumb.
       4091,
 
       # C4127: conditional expression is constant
       # This warning can in theory catch dead code and other problems, but
@@ skipping 250 matching lines @@
       }],
     ],
     'target_conditions': [
       ['chromium_code==0', {
         'variables': {
           'clang_warning_flags': [
             # Suppress unused variable warnings from third-party libraries.
             '-Wno-unused-variable',
           ],
         },
+        'msvs_disabled_warnings': [
+          # forcing value to bool 'true' or 'false' (performance warning)
+          4800,
+        ],
         'msvs_settings': {
           'VCCLCompilerTool': {
             'WarningLevel': '3',
           },
         },
         'conditions': [
           ['OS!="win"', {
             # Remove -Wextra for third-party code.
             'cflags!': [ '-Wextra' ],
           }],
@@ skipping 38 matching lines @@
       ],
     }],  # OS=="win"
     ["use_goma==1", {
       'make_global_settings': [
         ['CC_wrapper', '<(gomadir)/gomacc'],
         ['CXX_wrapper', '<(gomadir)/gomacc'],
       ],
     }],  # use_goma==1
   ],
 }