Suppress leak warning on name pushed into deliberaly leaked histogram

tools/heapcheck/suppressions.txt

 # There are three kinds of suppressions in this file.
 # 1. third party stuff we have no control over
 #
 # 2. intentional unit test errors, or stuff that is somehow a false positive
 # in our own code, or stuff that is so trivial it's not worth fixing
 #
 # 3. Suppressions for real chromium bugs that are not yet fixed.
 # These should all be in chromium's bug tracking system (but a few aren't yet).
 # Periodically we should sweep this file and the bug tracker clean by
 # running overnight and removing outdated bugs/suppressions.
@@ skipping 151 matching lines @@
    ...
    fun:ClientSocketPoolHistograms
 }
 {
    String name pushed into leaked CookieMonsterHistograms
    Heapcheck:Leak
    ...
    fun:basic_string
    fun:net::CookieMonster::InitializeHistograms
 }
+{
+   String name pushed into deliberately leaked StatsHistogram
+   Heapcheck:Leak
+   ...
+   fun:basic_string
+   fun:DiskCacheBackendTest_Histograms_Test::TestBody
+}
 #-----------------------------------------------------------------------
 # 3. Suppressions for real chromium bugs that are not yet fixed.
 # These should all be in chromium's bug tracking system (but a few aren't yet).
 # Periodically we should sweep this file and the bug tracker clean by
 # running overnight and removing outdated bugs/suppressions.
 {
    bug_31643
    Heapcheck:Leak
    fun:browser_sync::BookmarkModelWorker::CallDoWorkFromModelSafeThreadAndWait
    fun:Syncer::SyncShare
@@ skipping 1096 matching lines @@
 {
    bug_77885
    Heapcheck:Leak
    ...
    fun:cssyyparse
    fun:WebCore::CSSParser::parseSheet
    fun:WebCore::CSSStyleSheet::parseStringAtLine
    fun:WebCore::CSSStyleSheet::parseString
    fun:WebCore::parseUASheet
 }