* Update plugins/codemirror-editor from branch 'master'
to ee50e45b449e282ed78917175daf8b359da8d943
- Lazy load codemirror assets
Requires a relatively significant refactor of the attached function.
Uses promises instead of callbacks for loading to tests and later code
more legible and straightforward.
Bug: Issue 8764
Change-Id: I081564ff75c383bf042f77820e017ef04c8c313c