tests for callbacks created and detached
improving tests according to Dominic's notes
fixing minor typos
changing tests according to clarifications from Dimitri Glazkov
improving tests according to Dominic's notes
Extend the Document.createComment test a bit.
Remove race condition in test.
Fix order dependence in iframe test and fix use of setTimeout in many tests.
Insolated :valid and :invalid tests for more meaningfull results
Merge pull request #837 from sgrekhov/submission/unipro-custom-elements-8

Tests for Custom Elements created and detached callbacks
Don't probe IDBRequest.error if still pending
Update to latest wptserve
Separated form/fieldset selection as well
Merge pull request #886 from Ms2ger/Document-createComment

Extend the Document.createComment test a bit; r=plh
fixup! Fix order dependence in iframe test and fix use of setTimeout in many tests.
Merge pull request #890 from plehegar/valid-invalid-2

Insolated :valid and :invalid tests
Merge pull request #889 from w3c/jgraham/scheduler_fixups

Som fixes for the script scheduling tests
Fix worker onerror tests to catch window.onerror; expect 5 arguments; expect addEventListener to work; add a new test involving two documents.
Update to latest wptserve
addTextTrack assert_true mistake