This first PR refactors the props used by the search context CTA only.
There are couple of things going on here and they probably need some
discussion:
The SearchContextCtaPrompt component is not directly rendered by the
SearchContextDropdown anymore. The CTA is only used in the web app,
but the search context dropdown is also used in our vscode extension.
Instead of controlling the visibility of the CTA via the props that
the CTA uses (which requires knowledge about implementation details),
SearchBox now accepts the CTA as a prop itself. This makes the
component hierarchy flatter and allows allows the vscode extension to
simply pass nothing.
While the global state flags (hasUserAddedRepositories, etc) are not
necessarily search context specific, they have been added and are only
used by search context at the moment. Additionally, logic had to be
added to update those values.
I'm worried that by storing state in a "general" place (like the app
root, or a store just for those flags), other features will eventually
use flags without necessarily understanding their context/purpose.
Instead I'm proposing to adopt the concepts from the Flux
architecture: Components can dispatch actions/events which are handled
by an arbitrary number of stores. This leads to less coupled code by
separating state change intentions (events/actions) from their
effect (search context cta state change).
Specifically the dispatch function dispatches the event/action and
the search context cta store registers itself with the dispatcher.
The SearchContextCtaContainer provides the glue between the shared
component and the state implementation of the web app (this is not the
best example since the web app is the only platform to show the CTA at
this time).
Note: The structure of the code is a first draft. I don't want to imply that this is how we should structure events/actions (should probably standardize on "actions"). Everything is up for debate.
