Bug 1251529: Provide default constructor for ShellAllocationMetadataBuilder. r=orange

--HG--
extra : rebase_source : 98777531d8c40caa22b7bfe07f446a89256ce88a

js/src/builtin/TestingFunctions.cpp

@@ -1691,6 +1691,8 @@ DisplayName(JSContext* cx, unsigned argc, Value* vp)
 
 class ShellAllocationMetadataBuilder : public AllocationMetadataBuilder {
   public:
+    ShellAllocationMetadataBuilder() : AllocationMetadataBuilder() { }
+
     virtual JSObject* build(JSContext *cx, HandleObject,
                             AutoEnterOOMUnsafeRegion& oomUnsafe) const override;