Suppress deprecations while testing legacy code path

spec/context-menu-manager-spec.coffee

@@ -151,6 +151,13 @@ describe "ContextMenuManager", ->
       shouldDisplay = false
       expect(contextMenu.templateForEvent(dispatchedEvent)).toEqual []
 
+    describe "when the menus are specified in a legacy format", ->
+      beforeEach ->
+        jasmine.snapshotDeprecations()
+
+      afterEach ->
+        jasmine.restoreDeprecationsSnapshot()
+
       it "allows items to be specified in the legacy format for now", ->
         contextMenu.add '.parent':
           'A': 'a'