Bug 836301 - Add tracking for whether we have a non-trivial enter() trap. r=mrbkap

This will allow us to skip the virtual function call for non-security-wrapper
proxies, which are the cases where we care most about performance.

js/src/jsproxy.cpp

@@ -51,7 +51,8 @@ GetFunctionProxyConstruct(UnrootedObject proxy)
 
 BaseProxyHandler::BaseProxyHandler(void *family)
   : mFamily(family),
-    mHasPrototype(false)
+    mHasPrototype(false),
+    mHasPolicy(false)
 {
 }
 

js/src/jsproxy.h

@@ -51,9 +51,11 @@ class JS_FRIEND_API(Wrapper);
 class JS_FRIEND_API(BaseProxyHandler) {
     void *mFamily;
     bool mHasPrototype;
+    bool mHasPolicy;
   protected:
     // Subclasses may set this in their constructor.
     void setHasPrototype(bool aHasPrototype) { mHasPrototype = aHasPrototype; }
+    void setHasPolicy(bool aHasPolicy) { mHasPolicy = aHasPolicy; }
 
   public:
     explicit BaseProxyHandler(void *family);
@@ -63,6 +65,10 @@ class JS_FRIEND_API(BaseProxyHandler) {
         return mHasPrototype;
     }
 
+    bool hasPolicy() {
+        return mHasPolicy;
+    }
+
     inline void *family() {
         return mFamily;
     }

js/src/jswrapper.cpp

@@ -838,6 +838,7 @@ SecurityWrapper<Base>::SecurityWrapper(unsigned flags)
   : Base(flags)
 {
     Base::setSafeToUnwrap(false);
+    BaseProxyHandler::setHasPolicy(true);
 }
 
 template <class Base>