Roll clang 270823:273743.

build/common.gypi

Index: build/common.gypi
diff --git a/build/common.gypi b/build/common.gypi
index 934c137826be02c7218ef8bcb46e630731ef37cc..a6f80fbd64d1e4223a6fd8f5bd2596cd61da52ff 100644
--- a/build/common.gypi
+++ b/build/common.gypi
@@ -2640,6 +2640,9 @@
 
         # TODO(thakis): https://crbug.com/604888
         '-Wno-undefined-var-template',
+
+        # TODO(thakis): https://crbug.com/617318
+        '-Wno-nonportable-include-path',
       ],
     },
     'includes': [ 'set_clang_warning_flags.gypi', ],
@@ -3048,10 +3051,6 @@
         # TODO: Enable on Windows too, http://crbug.com/404525
         'variables': { 'clang_warning_flags': ['-Wexit-time-destructors']},
       }],
-      ['"<!(python <(DEPTH)/tools/clang/scripts/update.py --print-revision)"!="270823-1"', {
-        # TODO(thakis): https://crbug.com/617318
-        'variables': { 'clang_warning_flags': ['-Wno-nonportable-include-path']},
-      }],
       ['chromium_code==0', {
         'variables': {
           'clang_warning_flags': [