Move project-specific flags to common.gypi.

common.gypi

@@ -102,6 +102,7 @@
             '-Wno-return-type',
             '-Wno-gnu-folding-constant',
             '-Wno-shift-negative-value',
+            '-Wno-varargs', # https://git.io/v6Olj
           ],
         },
         'conditions': [
@@ -117,6 +118,7 @@
               '-Wno-deprecated-declarations',
               '-Wno-return-type',
               '-Wno-shift-negative-value',
+              '-Wno-varargs', # https://git.io/v6Olj
               # Required when building as shared library.
               '-fPIC',
             ],

toolchain.gypi

@@ -5,11 +5,6 @@
     # Set this to true when building with Clang.
     'clang%': 1,
 
-    'clang_warning_flags': [
-      '-Wno-undefined-var-template', # https://crbug.com/604888
-      '-Wno-varargs', # https://git.io/v6Olj
-    ],
-
     'variables': {
       # The minimum macOS SDK version to use.
       'mac_sdk_min%': '10.10',
@@ -109,7 +104,6 @@
         'cflags_cc': [
           '-std=c++11',
         ],
-        'cflags': [ '<@(clang_warning_flags)' ],
         'xcode_settings': {
           'CC': '<(make_clang_dir)/bin/clang',
           'LDPLUSPLUS': '<(make_clang_dir)/bin/clang++',
@@ -117,7 +111,6 @@
             '-fcolor-diagnostics',
           ],
 
-          'WARNING_CFLAGS': ['<@(clang_warning_flags)'],
           'GCC_C_LANGUAGE_STANDARD': 'c99',  # -std=c99
           'CLANG_CXX_LIBRARY': 'libc++',  # -stdlib=libc++
           'CLANG_CXX_LANGUAGE_STANDARD': 'c++11',  # -std=c++11