Auto merge of #289 - jdm:proxyfamily, r=nox

Add an API to retrieve the proxy family.

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Author: bors-servo

src/glue.rs

@@ -1,4 +1,5 @@
 use jsapi::*;
+use std::os::raw::c_void;
 
 pub enum Action { }
 unsafe impl Sync for ProxyTraps { }
@@ -265,4 +266,5 @@ extern "C" {
     pub fn CallUnbarrieredObjectTracer(trc: *mut JSTracer,
                                        objp: *mut *mut JSObject,
                                        name: *const ::libc::c_char);
+    pub fn GetProxyHandlerFamily() -> *const c_void;
 }

src/jsglue.cpp

@@ -629,6 +629,12 @@ IsProxyHandlerFamily(JSObject* obj)
     return js::GetProxyHandler(obj)->family() == &HandlerFamily;
 }
 
+const void*
+GetProxyHandlerFamily()
+{
+    return &HandlerFamily;
+}
+
 const void*
 GetProxyHandlerExtra(JSObject* obj)
 {