Factor out Q.noConflict test

This commit factors out the Q.noConflict test into two tests, each with one assertion. There is one test for node environments and another for browser environments where Q is used as a global.

spec/q-spec.js

@@ -2509,7 +2509,11 @@ describe("browser support", function () {
             // In this context the original value of Q is undefined
             Q.noConflict();
             expect(Q).toEqual(undefined);
-        } else {
+        }
+    });
+
+    it("throws an error if Q.noConflict is called in node", function () {
+        if (typeof window === 'undefined') {
             // If window is undefined the tests are being run in node, and
             // Q.noConflict should throw an error
             expect(Q.noConflict).toThrow();