Add PARSING_MEDIA_SEGMENT layout test for SourceBuffer mode

LayoutTests/http/tests/media/media-source/mediasource-sourcebuffer-mode.html

Index: LayoutTests/http/tests/media/media-source/mediasource-sourcebuffer-mode.html
diff --git a/LayoutTests/http/tests/media/media-source/mediasource-sourcebuffer-mode.html b/LayoutTests/http/tests/media/media-source/mediasource-sourcebuffer-mode.html
index 33e01574039dc101565da98d0e49edd4eaa63250..e4127fe6c5d1ff537f80be7174ba3c944c164b29 100644
--- a/LayoutTests/http/tests/media/media-source/mediasource-sourcebuffer-mode.html
+++ b/LayoutTests/http/tests/media/media-source/mediasource-sourcebuffer-mode.html
@@ -79,8 +79,53 @@
               });
           }, 'Test setting SourceBuffer.mode triggers parent MediaSource \'ended\' to \'open\' transition.');
 
-          // FIXME: Once enough Chromium implementation lands, add tests for at least confirming exception if append
-          // state is PARSING_MEDIA_SEGMENT (per 3.1 setting mode steps 6-7). See http://crbug.com/249422.
+          mediasource_testafterdataloaded(function(test, mediaElement, mediaSource, segmentInfo, sourceBuffer, mediaData)
+          {
+              var initSegment = MediaSourceUtil.extractSegmentData(mediaData, segmentInfo.init);
+              var fullMediaSegment = MediaSourceUtil.extractSegmentData(mediaData, segmentInfo.media[0]);
+              var truncateAt = Math.floor(segmentInfo.media[0].size * 0.95);  // e.g. first 11238 bytes of 11830

[acolwell GONE FROM CHROMIUM, 2014/01/14 18:20:27]

nit: Change the comment to something like 95% of the segment bytes so that it
can't become stale if we happen to reencode the file or change which test clip
that is used by default.

[wolenetz, 2014/01/14 19:30:44]

Done.

+              var partialMediaSegment = fullMediaSegment.subarray(0, truncateAt);
+              var mediaSegmentRemainder = fullMediaSegment.subarray(truncateAt);
+
+              // Append init segment.
+              test.expectEvent(sourceBuffer, 'updateend', 'Init segment append ended.');
+              sourceBuffer.appendBuffer(initSegment);
+
+              test.waitForExpectedEvents(function()
+              {
+                  assert_false(sourceBuffer.updating, 'updating attribute is false');
+                  assert_true(sourceBuffer.mode == 'segments');

[acolwell GONE FROM CHROMIUM, 2014/01/14 18:20:27]

nit: use assert_equals here and in similar checks below.

[wolenetz, 2014/01/14 19:30:44]

Done.

+                  sourceBuffer.mode = 'segments';  // No exception should occur.
+
+                  // Append first part of media segment.
+                  test.expectEvent(sourceBuffer, 'updateend', 'Partial media segment append ended.');
+                  sourceBuffer.appendBuffer(partialMediaSegment);
+              });
+
+              test.waitForExpectedEvents(function()
+              {
+                  assert_false(sourceBuffer.updating, 'updating attribute is false');
+                  assert_true(sourceBuffer.mode == 'segments');
+                  assert_throws('InvalidStateError',
+                      function() { sourceBuffer.mode = 'segments'; },
+                      'Setting valid sourceBuffer.mode while still parsing media segment threw InvalidStateError.');
+                  test.done();

[acolwell GONE FROM CHROMIUM, 2014/01/14 18:20:27]

nit: remove since it doesn't appear the test is actually done at this point.

[wolenetz, 2014/01/14 19:30:44]

Oh wow! This was a test debugging item I forgot to remove. Thanks for noticing
this.

+
+                  // Append remainder of media segment.
+                  test.expectEvent(sourceBuffer, 'updateend', 'Append ended of remainder of media segment.');
+                  sourceBuffer.appendBuffer(mediaSegmentRemainder);
+              });
+
+              test.waitForExpectedEvents(function()
+              {
+                  assert_false(sourceBuffer.updating, 'updating attribute is false');
+                  assert_true(sourceBuffer.mode == 'segments');
+                  sourceBuffer.mode = 'segments';  // No exception should occur.
+                  test.done();
+              });
+          }, 'Test setting SourceBuffer.mode while parsing media segment.');
+
+          // FIXME: Once 'sequence' mode implemented, add verification. See http://crbug.com/249422.
         </script>
     </body>
 </html>