Layout Test for basic MSE seek scenario.

LayoutTests/http/tests/media/media-source/mediasource-util.js

Index: LayoutTests/http/tests/media/media-source/mediasource-util.js
diff --git a/LayoutTests/http/tests/media/media-source/mediasource-util.js b/LayoutTests/http/tests/media/media-source/mediasource-util.js
index 456f012f4d99dc613dbdf3ac07f224d518097e76..181a35a55ee8e485b8034261f2de7eb2b03cbc35 100644
--- a/LayoutTests/http/tests/media/media-source/mediasource-util.js
+++ b/LayoutTests/http/tests/media/media-source/mediasource-util.js
@@ -4,6 +4,7 @@
         this.test_ = test;
         this.eventTargetList_ = [];
         this.waitCallbacks_ = [];
+        this.timeoutIDs_ = {};

[wolenetz, 2013/08/06 23:06:48]

This still needs removal :)

     };
 
     EventExpectationsManager.prototype.expectEvent = function(object, eventName, description)
@@ -35,6 +36,21 @@
         setTimeout(this.handleWaitCallback_.bind(this), 0);
     };
 
+    EventExpectationsManager.prototype.waitForTimeUpdate = function(mediaElement, callback)
+    {
+        var initialTime = mediaElement.currentTime;
+
+        var onTimeUpdate = this.test_.step_func(function()
+        {
+            if (mediaElement.currentTime != initialTime) {
+                mediaElement.removeEventListener('timeupdate', onTimeUpdate);
+                callback();
+            }
+        });
+
+        mediaElement.addEventListener('timeupdate', onTimeUpdate);
+    };
+
     EventExpectationsManager.prototype.expectingEvents = function()
     {
         for (var i = 0; i < this.eventTargetList_.length; ++i) {
@@ -176,6 +192,14 @@
             test.eventExpectations_.expectEvent(object, eventName, description);
         };
 
+        test.waitForTimeUpdate = function(mediaElement, callback)
+        // This function waits for a timeupdate event to be fired accompanied by
+        // a change in currentTime of the mediaElement. Only when both have
+        // occurred does it eventually invoke callback.
+        {
+            test.eventExpectations_.waitForTimeUpdate(mediaElement, callback);
+        }
+
         test.waitForExpectedEvents = function(callback)
         {
             test.eventExpectations_.waitForExpectedEvents(callback);
@@ -184,8 +208,14 @@
         var oldTestDone = test.done.bind(test);
         test.done = function()
         {
-            if (test.status == test.PASS)
+            // loop through and clear timeoutIDs

[wolenetz, 2013/08/06 23:06:48]

And clearing timeoutIDs needs removal too.

+            for (var i in test.eventExpectations_.timeoutIDs_) {
+                clearTimeout(test.eventExpectations_.timeoutIDs_[i]);
+            }
+            if (test.status == test.PASS) {
                 assert_false(test.eventExpectations_.expectingEvents(), "No pending event expectations.");
+                assert_equals(Object.keys(test.eventExpectations_.timeoutIDs_).length, 0);

[wolenetz, 2013/08/06 23:06:48]

And this line also needs removal.

+            }
             oldTestDone();
         };
     };