Bug 1496297 - Use |jit-test| skip-if as appropriate in jit-test/tests/ (r=jorendorff)

--HG--
extra : rebase_source : 3f1e7542a152a6992aa6ae7a5f24bd9442e3d21c

js/src/jit-test/tests/bug1213574.js

@@ -1,5 +1,4 @@
-if (helperThreadCount() === 0)
-    quit(0);
+// |jit-test| skip-if: helperThreadCount() === 0
 
 var lfGlobal = newGlobal();
 lfGlobal.offThreadCompileScript(`{ let x; throw 42; }`);

js/src/jit-test/tests/bug1366925.js

@@ -1,8 +1,7 @@
-// JS shell shutdown ordering
-
+// |jit-test| skip-if: helperThreadCount() === 0
 // Avoid crashing with --no-threads
-if (helperThreadCount() == 0)
-  quit();
+
+// JS shell shutdown ordering
 
 evalInWorker(`
   var lfGlobal = newGlobal();

js/src/jit-test/tests/bug1490638.js

@@ -1,6 +1,4 @@
-// |jit-test| allow-overrecursed
-if (helperThreadCount() == 0)
-    quit();
+// |jit-test| allow-overrecursed; skip-if: helperThreadCount() === 0
 
 evalInWorker(`
   function f() {