Bug 1110928, part 3 - Add a method to schedule the system zone for GC. r=terrence

MozReview-Commit-ID: 4L3iQMPWGNe

js/public/GCAPI.h

@@ -157,6 +157,12 @@ ExplainReason(JS::gcreason::Reason reason);
 extern JS_PUBLIC_API(void)
 PrepareZoneForGC(Zone* zone);
 
+/**
+ * Schedule the system zone to be collected as part of the next GC.
+ */
+extern JS_PUBLIC_API(void)
+PrepareSystemZoneForGC(JSContext* cx);
+
 /**
  * Schedule all zones to be collected in the next GC.
  */

js/src/jsgc.cpp

@@ -7120,6 +7120,12 @@ JS::PrepareZoneForGC(Zone* zone)
     zone->scheduleGC();
 }
 
+JS_PUBLIC_API(void)
+JS::PrepareSystemZoneForGC(JSContext* cx)
+{
+    PrepareZoneForGC(cx->runtime()->gc.systemZone);
+}
+
 JS_PUBLIC_API(void)
 JS::PrepareForFullGC(JSContext* cx)
 {