Adding unittest for the reference counting of WebMediaStreamDescriptor/Source

tools/valgrind/memcheck/suppressions.txt

Index: tools/valgrind/memcheck/suppressions.txt
diff --git a/tools/valgrind/memcheck/suppressions.txt b/tools/valgrind/memcheck/suppressions.txt
index 32fb9af605bc4b356723af8a25d97b291effc594..db034389b268809056aadbd824ab7510a8433ba8 100644
--- a/tools/valgrind/memcheck/suppressions.txt
+++ b/tools/valgrind/memcheck/suppressions.txt
@@ -5653,19 +5653,6 @@
    fun:_Z11BrowserMainRKN7content18MainFunctionParamsE
 }
 {
-   bug_111757
-   Memcheck:Leak
-   fun:malloc
-   fun:_ZN3WTF10fastMallocE*
-   ...
-   fun:_ZN7WebCore21MediaStreamDescriptor6createERKN3WTF6StringERKNS1_6VectorINS1_6RefPtrINS_17MediaStreamSourceEEEL*
-   fun:_ZN6WebKit24WebMediaStreamDescriptor10initializeERKNS_9WebStringERKNS_9WebVectorINS_20WebMediaStreamSourceEEE
-   fun:_ZN21PeerConnectionHandler28CreateWebKitStreamDescriptorEPN6webrtc20MediaStreamInterfaceE
-   fun:_ZN21PeerConnectionHandler19OnAddStreamCallbackEPN6webrtc20MediaStreamInterfaceE
-   fun:_ZN21PeerConnectionHandler11OnAddStreamEPN6webrtc20MediaStreamInterfaceE
-   fun:_ZN36PeerConnectionHandlerTest_Basic_Test8TestBodyEv
-}
-{
    bug_105580
    Memcheck:Leak
    fun:malloc_zone_malloc