Issue codemirror/google-modes#8

This is opt-in, the plugin needs to produce message_html instead of
message to be rendered as HTML.

This should help developers building this functionality out that may not
realize they need to source the linting library seperately.

Issue #3059

So that the addon doesn't try to put a single DOM node in two places

Closes #4848

Issue #4839

Closes #4839

Issue #4824

This prevents the test case search_expandingCaseFold from hanging in
Firefox 54 on Linux.

Issue #4819

Issue #4784

Issue #4787

Default this to true when the fat-cursor style is active.

Issue #4803

Since the vim bindins are depending on that

Issue #4712

Closes #4683

Add tag parameter to xml-fold findEnclosingTag to find enclosing tag of particular type.

Closes #4641

Issue #4627

Identifiers that contain the identifierQuote like a table named
my"table are now doublicated correctly (e.g. quoting produces:
"my""table"). This fixes 2 failing tests, but 2 others still fail.

Closes #4621

The identifier-quote that a language uses around identifiers can now
be defined using "identifierQuote" when defining a mimetype.
Previously, backticks where hardcoded, but this is not standard SQL
(which uses double quotes). For example, SQLite defines double quotes
as preferred way to quote identifiers:
http://sqlite.org/lang_keywords.html

... in a 3-editor view, by immediately syncing the scrolling from the
left to the right and vice-versa.

Issue #4607