Enable _FORTIFY_SOURCE=2 with clang for official builds (unless sanitizers are used).

BUG=392573
NOTRY=true

Review URL: https://codereview.chromium.org/377383004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@282200 0039d316-1c4b-4281-b951-d872f2087c98

build/common.gypi

@@ -3257,9 +3257,9 @@
           }],
           # _FORTIFY_SOURCE isn't really supported by Clang now, see
           # http://llvm.org/bugs/show_bug.cgi?id=16821.
-          # TODO(glider): once the bug is fixed, disable source fortification
-          # under the sanitizer tools only.
-          ['os_posix==1 and (OS!="linux" or clang!=1)', {
+          # It seems to work fine with Ubuntu 12 headers though, so use it
+          # in official builds.
+          ['os_posix==1 and (asan!=1 and msan!=1 and tsan!=1 and lsan!=1 and ubsan!=1) and (OS!="linux" or clang!=1 or buildtype=="Official")', {
             'target_conditions': [
               ['chromium_code==1', {
                 # Non-chromium code is not guaranteed to compile cleanly