Bug 809666: Define ctypes and perf properties on the 'this' object, not the global, when sharing globals. r=mrbkap

toolkit/components/perf/PerfMeasurement.cpp

@@ -8,6 +8,7 @@
 #include "mozilla/ModuleUtils.h"
 #include "nsMemory.h"
 #include "mozilla/Preferences.h"
+#include "mozJSComponentLoader.h"
 
 #define JSPERF_CONTRACTID \
   "@mozilla.org/jsperf;1"
@@ -44,6 +45,11 @@ SealObjectAndPrototype(JSContext* cx, JSObject* parent, const char* name)
   if (!JS_GetProperty(cx, parent, name, &prop))
     return false;
 
+  if (prop.isUndefined()) {
+    // Pretend we sealed the object.
+    return true;
+  }
+
   JSObject* obj = JSVAL_TO_OBJECT(prop);
   if (!JS_GetProperty(cx, obj, "prototype", &prop))
     return false;
@@ -59,10 +65,6 @@ InitAndSealPerfMeasurementClass(JSContext* cx, JSObject* global)
   if (!JS::RegisterPerfMeasurement(cx, global))
     return false;
 
-  // Can't freeze our global if it's shared.
-  if (Preferences::GetBool("jsloader.reuseGlobal"))
-    return true;
-
   // Seal up Object, Function, and Array and their prototypes.  (This single
   // object instance is shared amongst everyone who imports the jsperf module.)
   if (!SealObjectAndPrototype(cx, global, "Object") ||
@@ -84,11 +86,14 @@ Module::Call(nsIXPConnectWrappedNative* wrapper,
              jsval* vp,
              bool* _retval)
 {
-  JSObject* global = JS_GetGlobalForScopeChain(cx);
-  if (!global)
-    return NS_ERROR_NOT_AVAILABLE;
+  bool reusingGlobal = Preferences::GetBool("jsloader.reuseGlobal");
+  JSObject* targetObj = nullptr;
 
-  *_retval = InitAndSealPerfMeasurementClass(cx, global);
+  mozJSComponentLoader* loader = mozJSComponentLoader::Get();
+  nsresult rv = loader->FindTargetObject(cx, &targetObj);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  *_retval = InitAndSealPerfMeasurementClass(cx, targetObj);
   return NS_OK;
 }