[FF, Safari] Fix compatibility errors in tests

[maxbarnas]

Related: #201.

Failed automatic tests:

• Edge - 41
• Safari 9 - 39
• Firefox - 23
• Chrome - 1
• Opera - 1

[maxbarnas]

Results of tests

Series of fixes were made:

• Fixed compatibility issues in tests ckeditor5-ui#69
• Fixed compatibility issues in tests ckeditor5-utils#70
• Fixed compatibility issues in tests ckeditor5-engine#580
• Fixed compatibility issues in tests ckeditor5-core#17

Manual tests needed polyfill. Related PR will be published soon.

Firefox

• Unit tests
  • Enabling selectionchange event (which is soon to be enabled by default) solves last batch of failing tests
• Manual tests
  • No problems found

Safari

• Unit tests
  • Engine fixes are needed: [Safari] Fix failing engine tests #325
  • Problems with BabelJS and Unicode: https://github.com/ckeditor/ckeditor5-engine/issues/576
• Manual tests
  • Found one general error and one problem specifically with Safari https://github.com/ckeditor/ckeditor5-engine/issues/592

Edge

• Unit tests
  • Testing is postponed while Edge has regression errors Fix failed tests in Edge #323
• Manual tests
  • Editor runs, but there are plenty of unexpected behaviours, e.g. bolding selection that starts and the beginning of the line deletes that text

IE 11

• Failed and broken tests are almost in every package. I was unable to run the editor. Details: Check automated and manual tests compatibility with IE11 #329.

[Reinmar]

Super, thanks for the detailed output.

[Reinmar]

Beside the mentioned tests I have these issues:

• http://tests.ckeditor.dev:1030/build/modules/amd/tests/enter/entercommand [FF and Safari]
• http://tests.ckeditor.dev:1030/build/modules/amd/tests/link/ui/linkballoonpanel [FF only]

[Reinmar]

The enter command mentioned above is a regression on master, so it doesn't count. So the only failing test is the one in the link package. Let's move it to a separate ticket.

And for now, it means that we have FF and Safari clean with the exception of:

• https://github.com/ckeditor/ckeditor5-engine/issues/598
• https://github.com/ckeditor/ckeditor5-link/issues/29

So I'm closing this ticket as done (for FF and Safari).