Bump fetch-mock from 9.2.1 to 9.3.1

Remove legacy `annotation` component; rename `AnnotationOmega` -> `Annotation`

Fix spurious WebSocket disconnection errors

Bumps [fetch-mock](https://github.com/wheresrhys/fetch-mock) from 9.2.1 to 9.3.1.
- [Release notes](https://github.com/wheresrhys/fetch-mock/releases)
- [Commits](https://github.com/wheresrhys/fetch-mock/compare/v9.2.1...v9.3.1)
Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Remove browserify-shim

Revert "Bump prettier from 1.19.1 to 2.0.1"

This reverts commit 5cb9041d.

Add selectors for direct-linked annotation, group IDs

Bumps [prettier](https://github.com/prettier/prettier) from 1.19.1 to 2.0.1.
- [Release notes](https://github.com/prettier/prettier/releases)
- [Changelog](https://github.com/prettier/prettier/blob/master/CHANGELOG.md)
- [Commits](https://github.com/prettier/prettier/compare/1.19.1...2.0.1)
Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Bump @sentry/browser from 5.14.2 to 5.15.0

This is obsolete with the current version of the "hammerjs" package.

As a result of evolution of the libraries involved, this build tool is no
longer required.

A minor change was required in one test to adjust to the fact that
Angular now uses jqLite, as it does in the actual application, instead of jQuery.
This is because "jquery" is no longer automatically added to the bundle
when "angular" is added.

Remove "raf" dependency

Bump mocha from 7.1.0 to 7.1.1

Bumps [mocha](https://github.com/mochajs/mocha) from 7.1.0 to 7.1.1.
- [Release notes](https://github.com/mochajs/mocha/releases)
- [Changelog](https://github.com/mochajs/mocha/blob/master/CHANGELOG.md)
- [Commits](https://github.com/mochajs/mocha/compare/v7.1.0...v7.1.1)
Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Bumps [@babel/preset-env](https://github.com/babel/babel) from 7.8.7 to 7.9.0.
- [Release notes](https://github.com/babel/babel/releases)
- [Changelog](https://github.com/babel/babel/blob/master/CHANGELOG.md)
- [Commits](https://github.com/babel/babel/compare/v7.8.7...v7.9.0)
Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Bumps [eslint-plugin-react-hooks](https://github.com/facebook/react/tree/HEAD/packages/eslint-plugin-react-hooks) from 2.5.0 to 2.5.1.
- [Release notes](https://github.com/facebook/react/releases)
- [Changelog](https://github.com/facebook/react/blob/master/CHANGELOG.md)
- [Commits](https://github.com/facebook/react/commits/HEAD/packages/eslint-plugin-react-hooks)
Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Bumps [aws-sdk](https://github.com/aws/aws-sdk-js) from 2.641.0 to 2.643.0.
- [Release notes](https://github.com/aws/aws-sdk-js/releases)
- [Changelog](https://github.com/aws/aws-sdk-js/blob/master/CHANGELOG.md)
- [Commits](https://github.com/aws/aws-sdk-js/compare/v2.641.0...v2.643.0)
Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Bumps [@babel/preset-react](https://github.com/babel/babel) from 7.8.3 to 7.9.1.
- [Release notes](https://github.com/babel/babel/releases)
- [Changelog](https://github.com/babel/babel/blob/master/CHANGELOG.md)
- [Commits](https://github.com/babel/babel/compare/v7.8.3...v7.9.1)
Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Bumps [@babel/core](https://github.com/babel/babel) from 7.8.7 to 7.9.0.
- [Release notes](https://github.com/babel/babel/releases)
- [Changelog](https://github.com/babel/babel/blob/master/CHANGELOG.md)
- [Commits](https://github.com/babel/babel/compare/v7.8.7...v7.9.0)
Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Bumps [@octokit/rest](https://github.com/octokit/rest.js) from 17.1.0 to 17.1.1.
- [Release notes](https://github.com/octokit/rest.js/releases)
- [Commits](https://github.com/octokit/rest.js/compare/v17.1.0...v17.1.1)
Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Bumps [@sentry/browser](https://github.com/getsentry/sentry-javascript) from 5.14.2 to 5.15.0.
- [Release notes](https://github.com/getsentry/sentry-javascript/releases)
- [Changelog](https://github.com/getsentry/sentry-javascript/blob/master/CHANGELOG.md)
- [Commits](https://github.com/getsentry/sentry-javascript/compare/5.14.2...5.15.0)
Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Remove feature-flag switch: Render `AnnotationOmega` in all cases

Fix browser warnings about an abnormal disconnection when the WS
connection is closed normally by calling `socket.close()`.

When `WebSocket#close` is called with no code, the browser will send a
close frame to the server with no payload. This is valid. On the backend
ws4py translates this into a 1005 status code, which is also correct.
However, ws4py then responds with the server's close frame and instead
of sending no payload, it sends a close frame with a payload that has a
1005 status. This is not allowed by the spec and results in errors in
the browser about an abnormal disconnection.

Although the proper fix for this needs to happen on the server, the
simplest solution right now is to set a status code in the client and
ws4py will respond with the same status code in the server's close
frame.

As part of this, refactor the tests to clearly separate the tests for
what happens when the browser/server closes the connection vs when the
client closes the connection.

Don't warn if the WebSocket is closed with a "going away" code (1001).
This is a "normal" closure and, per the WebSocket RFC [1], can happen
when the browser navigates away from the current page.

[1] https://tools.ietf.org/html/rfc6455#section-7.4.1

This used to have an effect when we used proxyquire for mocking. It does
nothing now.

requestAnimationFrame is supported natively [1] by all the browsers we
support.

[1] https://caniuse.com/#search=requestanimationframe

Add keyboard navigation to MarkdownEditor to improve a11y

- `arrow left`, `arrow right`, `home` and `end` keys are all supported and modeled after https://www.w3.org/TR/wai-aria-practices/examples/toolbar/toolbar.html

- Add roving tabIndex value for all toolbar elements.

This is a pre-requisite to removing the feature flag

This is part of eliminating direct access to store state, and a tiny
piece of simplifying the `groups` service.

Remove "invisible threads" logic

Remove "extend" dependency

This had been replaced with object spread or `Object.assign` apart from
in one instance.

Tune virtual thread list debouncing

When scrolling through a long list of annotations quickly, the sidebar
could display blank space for a long period of time. This was happening
because the debounced update function waited for a period of at least
20ms with no "scroll" events, and a gap of that length could take some
time to appear if there was a queue of scroll events being delivered.

Fix the issue by adding an upper bound of 100ms after a scroll event before
recalculating the list of visible threads.

Also make sure to cancel any pending updates after the `detach` method
is called.