Update from https://crrev.com/308331

third_party/mesa/mesa.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.
 
 {
   'variables': {
     'generated_src_dir': 'src/chromium_gensrc',
   },
   'target_defaults': {
     'defines': [
@@ skipping 114 matching lines @@
         'mesa_headers',
       ],
       # TODO(scottmg): http://crbug.com/143877 These should be removed if
       # Mesa is ever rolled and the warnings are fixed.
       'msvs_disabled_warnings': [
           4005, 4018, 4065, 4090, 4099, 4291, 4345, 4267,
       ],
       'variables': {
         'clang_warning_flags': [
           '-Wno-tautological-constant-out-of-range-compare',
+          '-Wno-mismatched-tags',  # Fixed upstream.
         ],
         'clang_warning_flags_unset': [
           # Don't warn about string->bool used in asserts.
           '-Wstring-conversion',
         ],
       },
       'sources': [
         '<(generated_src_dir)/mesa/main/dispatch.h',
         'src/src/glsl/ast_expr.cpp',
         'src/src/glsl/ast_function.cpp',
@@ skipping 117 matching lines @@
         'mesa_libglslcommon',
       ],
       # TODO(scottmg): http://crbug.com/143877 These should be removed if
       # Mesa is ever rolled and the warnings are fixed.
       'msvs_disabled_warnings': [
           4005, 4018, 4090, 4099, 4146, 4291, 4305, 4334, 4748, 4267,
       ],
       'variables': {
         'clang_warning_flags': [
           '-Wno-tautological-constant-out-of-range-compare',
+          '-Wno-absolute-value',  # Fires on st_atom_array.c, might be a bug
+          '-Wno-mismatched-tags',  # Fixed upstream.
         ],
         'clang_warning_flags_unset': [
           # Don't warn about string->bool used in asserts.
           '-Wstring-conversion',
         ],
       },
       'sources': [
         '<(generated_src_dir)/mesa/builtin_function.cpp',
         '<(generated_src_dir)/mesa/glapi_mapi_tmp_shared.h',
         'src/src/mapi/mapi/entry.c',
@@ skipping 446 matching lines @@
                 '<(PRODUCT_DIR)/libosmesa.so',
                 '<(SHARED_LIB_DIR)/libosmesa.so',
               ],
             },
           ],
         },
       ],
     }],
   ],
 }