Bug 1009788 - Allow js::TriggerZoneGC() to be called from parallel threads again r=terrence

js/src/jit-test/tests/parallel/bug1009788.js

@@ -0,0 +1,5 @@
+for (var a = 0; a < 2000; a++) {
+    Array.buildPar(500, (function() {
+        return {}
+    }))
+}

js/src/jsgc.cpp

@@ -2011,7 +2011,7 @@ GCRuntime::triggerGC(JS::gcreason::Reason reason)
 bool
 js::TriggerZoneGC(Zone *zone, JS::gcreason::Reason reason)
 {
-    return zone->runtimeFromMainThread()->gc.triggerZoneGC(zone,reason);
+    return zone->runtimeFromAnyThread()->gc.triggerZoneGC(zone,reason);
 }
 
 bool