Suppress uninitialized read report in VideoDestinationHandlerTest.Open on Mac OS

BUG=244420
R=timurrrr@chromium.org
NOTRY=true

Review URL: https://chromiumcodereview.appspot.com/15912008

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@202567 0039d316-1c4b-4281-b951-d872f2087c98

tools/valgrind/memcheck/suppressions_mac.txt

@@ -2362,3 +2362,11 @@
    fun:_ZN5media19ScreenCaptureDevice4Core9DoCaptureEv
    fun:_ZN5media19ScreenCaptureDevice4Core7DoStartEv
 }
+{
+   bug_244420
+   Memcheck:Uninitialized
+   ...
+   fun:_ZN9talk_baseL8ToStringIyEESsRKT_
+   fun:_ZN7content23VideoDestinationHandler4OpenEPNS_28MediaStreamDependencyFactoryEPNS_28MediaStreamRegistryInterfaceERKSsPPNS_20FrameWriterInterfaceE
+   fun:_ZN7content37VideoDestinationHandlerTest_Open_Test8TestBodyEv
+}