Next to each pinned message, we want to display a pin icon in the color of the thread. To do this, one main change that was made is we need to determine whether the `ComposedMessage` (`Message` ->
`TextMessage` or `MultimediaMessage` -> `ComposedMessage`) is rendered within a modal, or just in chat. This is because we consider two scenarios:
1) The message is displayed in the toggle pin modal or the thread pinned messages modal - here, we want to avoid displaying the pin icon next to messages
2) The message is rendered in the chat view, and there we want to display the pin icon next to messages.
As opposed to using a Context, I figured that that propagating the props through the three components in the rendering hierarchy would be the most efficient, so that's what this diff does.