Added kapt plugin + dependencies in order to be able to use Room
Added recent apps to share fragment (top 6)
Extracted dimens of share_to_apps.xml in the dimens file

* For #6413: Adds more snackbar positioning logic

* Refactor

* For #6413: Fixes snackbar positionining for bottom toolbar

* For #6413: Cleans up snackbar usage

Plus a bunch of docs and refactoring

* For #2754 Add tab cards to share sheet

* For #2754: Fix background near rounded corners and ShareButtonAppearanceTest

* Add license to share_tab_item

* For #5092 - Show a Snackbar with retry option if sharing to devices fails

ShareController will contain all the business logic for checking the result
status of the `share to device` operations. When this fails it will show a
snackbar which also offer the possibility to retry the just failed operation.
To allow this even in the event the user has closed the share fragment we'll
use a GlobalScope's coroutine.
Refactored out the TabsSharedCallback from ShareFragment because otherwise we
would have neede to sent through that the just failed operation. After the
refactor the ShareController is solely responsable for showing the right
snackbar and handling the retry actions.

* For #5092 - Refactor ShareControllerTest

* For #5092: Adds color theming of snackbars

Navigation between app fragments uses ShareTab as arguments. The newly used
SendTabUseCases uses TabData which is not Parcelable.
For minimal changes we'll keep both data classes and ShareController will know
how to map between the two.
Removed the `sessionId` property of ShareTab as it isn't needed anymore.

`ShareController` defines a contract with all possible `ShareFragment`'s
behavior changes and comes with a default implementation -
`DefaultShareController`.
It is to be delegated by all `ShareFragment`s contained Views' Interactors
following any user interactions.

ShareFragment which acts as a container would contain all business logic needed
for populating it's Views.
Data initialization should be done only once since the app state has no reason
to change after the ShareFragment is created and is done as soon as possible,
in onAttach().
Because of the expected short lifespan of this fragment, given the fact that
the state has no reason to change and we handle orientation changes ourselves
to keep things simple I didn't use a ViewModel to persist the state.

In an effort to respect the initial MVI architecture I've broken the
complex `AppShareView` in 3 separate Views
- `ShareCloseView`
- `ShareToAccountDevicesView`
- `ShareToAppsView`
They are standalone Views (extending LayoutContainer) which know nothing about
each other or their parent and so offer their container the possibility to
order or display them in any form later.
According to the lib-state contract they are only responsible to
- inflate themselves in their injected containerView
- render a certain state (to be added in later commits)
- delegate all user interaction to an associated Interactor

* For #2886: Fix sending multiple tabs to another device

* Update share methods to use new API

* Closes #2782: Hide send tab when no devices available

* For #2752: Enabled send tab for debug and nightly builds

* For #2753: Add Send Tab functionality to UI

* Closes #2751: Add custom app share sheet

* Closes #2753: Add send tab devices to share sheet

* Closes #2752: Add build flag for send tab

* Replace Context.share with ShareFragment