Added suppression for WebLayerTreeViewImpl::setShowDebugBorders().

TBR=zhaoqin
BUG=175985

Review URL: https://codereview.chromium.org/12260007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@182199 0039d316-1c4b-4281-b951-d872f2087c98

tools/valgrind/memcheck/suppressions.txt

@@ -6531,3 +6531,9 @@
    ...
    fun:_ZN18ValueStoreFrontend*
 }
+{
+    bug_175985
+    Memcheck:Uninitialized
+    fun:_ZN2cc13LayerTreeHost13setDebugStateERKNS_19LayerTreeDebugStateE
+    fun:_ZN6WebKit20WebLayerTreeViewImpl19setShowDebugBordersEb
+}