Make w3cwrapper.js's done() match the semantics in testharness.js

LayoutTests/media/W3C/w3cwrapper.js

Index: LayoutTests/media/W3C/w3cwrapper.js
diff --git a/LayoutTests/media/W3C/w3cwrapper.js b/LayoutTests/media/W3C/w3cwrapper.js
index 203c74f077329ee34a1fac1c23fcef200deb28d3..bee0129cfbba100f33eab6ac55ecfd739f081325 100644
--- a/LayoutTests/media/W3C/w3cwrapper.js
+++ b/LayoutTests/media/W3C/w3cwrapper.js
@@ -7,7 +7,7 @@ function getAudioURI(dummy) {
   return "../../../content/test.wav";
 }
 
-function testStep(testFunction){
+function testStep(testFunction) {
   try {
     testFunction();
   } catch (e) {
@@ -15,6 +15,15 @@ function testStep(testFunction){
   }
 }
 
+function testDone() {
+  // match the semantics of testharness.js done(), where nothing that

[ddorwin, 2014/03/20 17:25:03]

nit: Match

[philipj_slow, 2014/03/21 03:00:52]

Done.

+  // happens after that call has any effect on the test result.

[ddorwin, 2014/03/20 17:25:03]

Does this mean that W3C tests assume the test terminates but other Blink layout
tests do not? If so, the latter seems broken but would probably be much riskier
to fix.

Or maybe this particular test is broken because it does not clear the event
handler or set some variable the first time it is called. Or maybe the W3C
testharness.js takes on this responsibility where as Blink tests have been
written to clean themselves up.

[philipj_slow, 2014/03/21 03:00:52]

It means that assertions or exceptions after t.done() in testharness.js
async_test are ignored. This test would pass:

async_test(function(t) {
  t.done();
  assert_unreached();
  throw new Error();
});
The test looked fine to me. It's just that since testharness.js has this
behavior, tests don't need to worry about clearing event handlers or anything
like that. I assume that tests written for each framework work as they should,
for the most part. (FWIW, I prefer testharness.js, precisely because you don't
need to worry about what happens after the test is finished.)

+  if (!window.wasFinishJSTestCalled) {
+    finishJSTest();
+    assert_equals = assert_true = assert_false = function() { };
+  }
+}
+
 function test(testFunction) {
   description(document.title);
   testStep(testFunction);
@@ -25,7 +34,7 @@ function async_test(title, options) {
   description(title);
   return {
     step: testStep,
-    done: finishJSTest
+    done: testDone
   }
 }