Suppress invalid read/write in Mac screen capture test

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 # running overnight and removing outdated bugs/suppressions.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 2335 matching lines @@
 {
    bug_231969
    Memcheck:Uninitialized
    fun:rangematch
    fun:fnmatch1
    fun:fnmatch1
    fun:fnmatch$UNIX2003
    fun:_ZN9file_util14FileEnumerator4NextEv
    fun:_ZN10disk_cache11SimpleIndex15RestoreFromDiskERKN4base8FilePathE
 }
+{
+   bug_244102
+   Memcheck:Unaddressable
+   ...
+   fun:_ZN5media12_GLOBAL__N_117ScreenCapturerMac10GlBlitFastERKN6webrtc12DesktopFrameERKNS2_13DesktopRegionE
+   fun:_ZN5media12_GLOBAL__N_117ScreenCapturerMac7CaptureERKN6webrtc13DesktopRegionE
+   fun:_ZN5media19ScreenCaptureDevice4Core9DoCaptureEv
+   fun:_ZN5media19ScreenCaptureDevice4Core7DoStartEv
+}