Valgrind reports leaks in CGContextShowGlyphsWithAdvances on Mac

tools/valgrind/memcheck/suppressions_mac.txt

 # There are three kinds of suppressions in this file:
 # 1. Third party stuff we have no control over.
 #
 # 2. Intentional unit test errors, 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.
 # Periodically we should sweep this file and the bug tracker clean by
 # running overnight and removing outdated bugs/suppressions.
@@ skipping 1224 matching lines @@
    ...
    fun:CFBundlePreflightExecutable
 }
 {
    bug_75136b
    Memcheck:Addr4
    ...
    fun:CFBundlePreflightExecutable
 }
 {
-   bug_75142
+   bug_75142a
    Memcheck:Addr4
    ...
    fun:CGContextShowGlyphsWithAdvances
 }
 {
+   bug_75142b
+   Memcheck:Leak
+   ...
+   fun:CGContextShowGlyphsWithAdvances
+}
+{
    bug_75714_a
    Memcheck:Addr8
    ...
    fun:argb32_mark
    fun:ripl_BltShape
    ...
    fun:ripc_Render*
    ...
    fun:-[NSView _drawRect:clip:]
    fun:-[NSView _recursiveDisplayAllDirtyWithLockFocus:visRect:]
@@ skipping 715 matching lines @@
    fun:_ZNSt8_Rb_treeIjSt4pairIKjiESt10_Select1stIS2_ESt4lessIjESaIS2_EE11_M_get_nodeEv
    fun:_ZNSt8_Rb_treeIjSt4pairIKjiESt10_Select1stIS2_ESt4lessIjESaIS2_EE14_M_create_nodeERKS2_
    fun:_ZNSt8_Rb_treeIjSt4pairIKjiESt10_Select1stIS2_ESt4lessIjESaIS2_EE9_M_insertEPSt18_Rb_tree_node_baseSA_RKS2_
    fun:_ZNSt8_Rb_treeIjSt4pairIKjiESt10_Select1stIS2_ESt4lessIjESaIS2_EE13insert_uniqueERKS2_
    fun:_ZNSt8_Rb_treeIjSt4pairIKjiESt10_Select1stIS2_ESt4lessIjESaIS2_EE13insert_uniqueESt17_Rb_tree_iteratorIS2_ERKS2_
    fun:_ZNSt3mapIjiSt4lessIjESaISt4pairIKjiEEE6insertESt17_Rb_tree_iteratorIS4_ERKS4_
    fun:_ZNSt3mapIjiSt4lessIjESaISt4pairIKjiEEEixERS3_
    fun:_ZN18RenderWidgetHelper17AllocTransportDIBEmbPN4base14FileDescriptorE
    fun:_ZN19RenderMessageFilter19OnAllocTransportDIBEmbPN4base14FileDescriptorE
 }