Remove the suppression for a Issue 24307: Data race on reference counter

BUG=24307
TEST=tsan mac bot should remain green - (http://build.chromium.org/buildbot/waterfall/waterfall?builder=Linux+Tests+(tsan)&builder=Chromium+Mac+(tsan))

Review URL: http://codereview.chromium.org/333029

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@30120 0039d316-1c4b-4281-b951-d872f2087c98

tools/valgrind/tsan/suppressions.txt

@@ -54,12 +54,6 @@
   fun:*logging*SetMinLogLevel*
 }
 
-{
-  bug_24307
-  ThreadSanitizer:Race
-  fun:*RefCounted*disk_cache*File*
-}
-
 {
   bug_24419
   ThreadSanitizer:Race