Add alternate heapcheck suppression for PlatformThread::SetName

The unwinder gets off track coming out of libstdc++'s basic_string ctor
since upgrading the bot to Precise.

TBR=timurrrr@chromium.org
BUG=136936

Review URL: https://codereview.chromium.org/12301024

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@183225 0039d316-1c4b-4281-b951-d872f2087c98

tools/heapcheck/suppressions.txt

@@ -1383,13 +1383,21 @@
    fun:ui::InputMethodIBus::Init
 }
 {
-   bug_136936
+   bug_136936_a
    Heapcheck:Leak
    ...
    fun:std::basic_string::_Rep::_S_create
    ...
    fun:base::PlatformThread::SetName
 }
+{
+   bug_136936_b
+   Heapcheck:Leak
+   ...
+   fun:std::basic_string::_Rep::_S_create
+   ...
+   fun:base::PlatformThread::CurrentId
+}
 {
    bug_143565
    Heapcheck:Leak