* Accessibility: Make the native toolbox item communicate that it is a button.

* Accessibility: If an item is toggled, mark it as selected for accessibility

* Accessibility: Make the toolbox a toolbar for accessibility

* Accessibility: Mark the bottom sheet as a menu for accessibility

* Fix typo, AccessibilityRole, not AccessibleRole

* Statement fix

* Appease the linter

* Fix linting errors for real this time

- re-add thepand icon, shaped like a pill
- round top corners

This has the side effect of showing the bottom navbar when the toolbox is open,
which is a nice thing since back is accessible.

React Native doesn't define __filename nor __dirname so do it artisanally. In
addition, this helps with centralizing the configuration passed to loggers.

Avoid using a Modal since those create trouble with the view hierarchy.

🔥🔥🔥

Using anything non-serializable for action types is discouraged:
https://redux.js.org/faq/actions#actions

In fact, this is the Flow definition for dispatching actions:

declare export type DispatchAPI<A> = (action: A) => A;
declare export type Dispatch<A: { type: $Subtype<string> }> = DispatchAPI<A>;

Note how the `type` field is defined as a subtype of string, which Symbol isn’t.

We no longer need it since Rect 16 takes care of passing the context around.
It's also deprecated: https://atlaskit.atlassian.com/packages/core/layer-manager

The package now requires using a ModalTransition component
to handle animations. The existing DialogContainer component
has been split into native and web implementations to support
this change.

For the most part the changes are taking the "static propTypes" declaration off
of components and declaring them as Flow types. Sometimes to support flow some
method signatures had to be added. There are some exceptions in which more had
to be done to tame the beast:
- AbstractVideoTrack: put in additional truthy checks for videoTrack.
- Video: add truthy checks for the _videoElement ref.
- shouldRenderVideoTrack function: Some component could pass null for the
  videoTrack argument and Flow wanted that called out explicitly.
- DisplayName: Add a truthy check for the input ref before acting on it.
- NumbersList: Move array checks inline for Flow to comprehend array methods
  could be called. Add type checks in the Object.entries loop as the value is
  assumed to be a mixed type by Flow.
- AbstractToolbarButton: add additional truthy check for passed in type.