Add suppressions for Mac UI valgrind bots

tools/valgrind/memcheck/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 # running overnight and removing outdated bugs/suppressions.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 296 matching lines @@
 }
 {
    bug_23314
    Memcheck:Addr2
    fun:sqlite3PcacheClearSyncFlags
    fun:syncJournal
    fun:sqlite3PagerCommitPhaseOne
    fun:sqlite3BtreeCommitPhaseOne
 }
 {
+   bug_23314b
+   Memcheck:Addr4
+   fun:sqlite3PcacheClearSyncFlags
+   fun:syncJournal
+   fun:sqlite3PagerCommitPhaseOne
+   fun:sqlite3BtreeCommitPhaseOne
+}
+{
    # Valgrind doesn't grok clone quite yet on x64,
    # see https://bugs.kde.org/show_bug.cgi?id=117564
    valgrind_bug_117564
    Memcheck:Param
    clone(child_tidptr)
    fun:clone
    fun:_ZN7testing8internal13ExecDeathTest10AssumeRoleEv
 }
 
 #-----------------------------------------------------------------------
@@ skipping 731 matching lines @@
    fun:_Z10cssyyparsePv
    fun:_ZN7WebCore9CSSParser10parseSheetEPNS_13CSSStyleSheetERKNS_6StringE
 }
 {
    bug_26216
    Memcheck:Leak
    fun:_Znw*
    fun:_ZN9Extension25LoadExtensionActionHelperEPK15DictionaryValuePSs
    fun:_ZN39ExtensionTest_LoadPageActionHelper_Test8TestBodyEv
 }