remove JS gc roots on wrappedjs objects during xpconnect shutdown to avoid needless rooting and noise in root leak logs. bug 55426. a=brendan@mozilla.org r=mccabe@netscape.com

js/src/xpconnect/src/xpcjsruntime.cpp

@@ -71,10 +71,11 @@ DEBUG_WrapperChecker(JSHashEntry *he, intN i, void *arg)
 JS_STATIC_DLL_CALLBACK(intN)
 WrappedJSShutdownMarker(JSHashEntry *he, intN i, void *arg)
 {
+    JSRuntime* rt = (JSRuntime*) arg;
     nsXPCWrappedJS* wrapper = (nsXPCWrappedJS*)he->value;
     NS_ASSERTION(wrapper, "found a null JS wrapper!");
     NS_ASSERTION(wrapper->IsValid(), "found an invalid JS wrapper!");
-    wrapper->SystemIsBeingShutDown();
+    wrapper->SystemIsBeingShutDown(rt);
     return HT_ENUMERATE_NEXT;
 }
 
@@ -107,7 +108,7 @@ XPCJSRuntime::~XPCJSRuntime()
         if(count)
             printf("deleting XPCJSRuntime with %d live wrapped JSObject\n", (int)count);        
 #endif
-        mWrappedJSMap->Enumerate(WrappedJSShutdownMarker, nsnull); 
+        mWrappedJSMap->Enumerate(WrappedJSShutdownMarker, mJSRuntime); 
         delete mWrappedJSMap;
     }
 

js/src/xpconnect/src/xpcprivate.h

@@ -775,7 +775,7 @@ public:
     nsXPCWrappedJS* Find(REFNSIID aIID);
 
     JSBool IsValid() const {return mJSObj != nsnull;}
-    void SystemIsBeingShutDown();
+    void SystemIsBeingShutDown(JSRuntime* rt);
 
     virtual ~nsXPCWrappedJS();
 private:

js/src/xpconnect/src/xpcwrappedjs.cpp

@@ -268,7 +268,7 @@ nsXPCWrappedJS::~nsXPCWrappedJS()
                     map->Remove(this);
                 }
             }
-                JS_RemoveRootRT(rt->GetJSRuntime(), &mJSObj);
+            JS_RemoveRootRT(rt->GetJSRuntime(), &mJSObj);
         }
         NS_IF_RELEASE(mClass);
     }
@@ -328,7 +328,7 @@ nsXPCWrappedJS::GetIID(nsIID** iid)
 }
 
 void 
-nsXPCWrappedJS::SystemIsBeingShutDown()
+nsXPCWrappedJS::SystemIsBeingShutDown(JSRuntime* rt)
 {
     // XXX It turns out that it is better to leak here then to do any Releases 
     // and have them propagate into all sorts of mischief as the system is being
@@ -340,12 +340,15 @@ nsXPCWrappedJS::SystemIsBeingShutDown()
 
     // NOTE: that mClass is retained so that GetInterfaceInfo can continue to 
     // work (and avoid crashing some platforms).
-
     mJSObj = nsnull;
     
+    // There is no reason to keep this root any longer. Since we've cleared
+    // mJSObj our dtor will not remove the root later. So, we do it now. 
+    JS_RemoveRootRT(rt, &mJSObj);
+
     // Notify other wrappers in the chain.
     if(mNext)
-        mNext->SystemIsBeingShutDown();
+        mNext->SystemIsBeingShutDown(rt);
 }
 
 /***************************************************************************/