Use early expansion for debug_optimize and release_optimize

BUG=139118
TEST=none

Review URL: https://chromiumcodereview.appspot.com/10828084

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@149677 0039d316-1c4b-4281-b951-d872f2087c98

build/common.gypi

@@ -2059,7 +2059,7 @@
               'release_valgrind_build%': 0,
             },
             'cflags': [
-              '-O>(release_optimize)',
+              '-O<(release_optimize)',
               # Don't emit the GCC version ident directives, they just end up
               # in the .comment section taking up binary size.
               '-fno-ident',