Exclude src/test-util from code coverage metrics

Our current policy is not to include test-only code in coverage metrics.

Add preStart method to cross-origin-rcp module

When called, allows any incoming rpc request to wait in a queue and be proceeded a short time later when the actual start() method is called. This prevents potential timeouts from incoming RPC requests from LMS (or similar) that arrive after we tipped off the parent frame with a fetchConfig outgoing request but before startServer() is called.

- Rename start() to startServer()
- Use newer module export standard that matches the rest of the app

Remove $location service and annotation subcomponents from sidebar entry module

Remove unused `permissions` service

After `Annotation` was converted to Preact, the subcomponents no longer
need to be wrapped and exposed to Angular.

This built-in Angular service is no longer used, so remove the code to
configure it and expose it to other services.

Use `permissions` util instead

Replace angular `toastr` with preact-compatible toast messages

Replace Angular router

Bump fetch-mock from 9.2.1 to 9.3.1

* preact-compatible
* more accessible

Fix an issue where the route was set before the initial profile and
groups fetch had completed, which could result in the WebSocket
connection being created and then immediately torn down and re-created
on startup.

The route was set too soon because Safari and Chrome emit a "popstate"
event on page load, which triggered a call to `router.sync()` before the
call to `sync()` made by `setupRoute` in src/sidebar/index.js after the
initial profile and groups load.

The solution is to only add the "popstate" listener after the initial
call to `sync()`.

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

See https://github.com/hypothesis/client/pull/1906#discussion_r394340280
and https://github.com/hypothesis/client/pull/1906#discussion_r394341565

Implement a replacement for the Angular JS router which will enable the
root components of the app to be more easily migrated to Preact in future.
Since the app only has three routes with very simple parameters, we
don't yet need a fully-fledged router implementation but can get by with
some pretty basic URL parsing.

 - Introduce a store module which holds the currently active route
   (`null`, "sidebar", "annotation" or "stream") and any parameters of
   that route.

   This state replaces the `isSidebar` boolean in the `viewer` module,
   since whether the app is the sidebar can be determined by checking
   the active route name.

 - Add a `router` service which handles synchronizing the store route
   with the current URL (via the `sync` method or in response to a
   `popstate` DOM event) or updating the URL and active route in the
   store (via the `navigate` method).

 - Modify the `<hypothesis-app>` component to fetch the active route
   from the store and use it to conditionally render the appropriate
   content component. This replaces the Angular router configuration
   that used to be in `src/sidebar/index.js`

 - Change the places that used to read or update the current route to
   read the active route and route params from the store (`store.{route,
   routeParams}`) and switch the current route by using the `router` service
   (`router.navigate`)

 - Remove the unused angular-route package

Fixes #1878

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>