add typecasts to reduce warnings on Macintosh compiler (r/a mike mccabe)

js/src/jslock.c

@@ -336,7 +336,7 @@ js_SuspendThread(JSThinLock *p)
 	PR_Unlock(fl->slock);
 	return 1;
     }
-    stat = PR_WaitCondVar(fl->svar,PR_INTERVAL_NO_TIMEOUT);
+    stat = (JSStatus)PR_WaitCondVar(fl->svar,PR_INTERVAL_NO_TIMEOUT);
     if (stat == JS_FAILURE) {
 	fl->susp--;
 	return 0;
@@ -362,7 +362,7 @@ js_ResumeThread(JSThinLock *p)
 	PR_Unlock(fl->slock);
 	return;
     }
-    stat = PR_NotifyCondVar(fl->svar);
+    stat = (JSStatus)PR_NotifyCondVar(fl->svar);
     JS_ASSERT(stat != JS_FAILURE);
     PR_Unlock(fl->slock);
 }