[ci no changelog needed]
[Task link](https://www.pivotaltracker.com/story/show/182955595)
This PR implements variable column widths in the new Grid View component. We need this feature to quickly implement various parts of the UI, including the breadcrumbs panel of the component browser.
There are two ways to change the width of the specific column:
1. "From the outside", using the `set_column_width` endpoint of the Grid View
2. "From the inside", using the `override_column_width` endpoint of the EntryFrp.
Both ways work similarly, but the latter is helpful for our breadcrumbs implementation, as it allows for entry to decide on the width of the column by its content.
See the screencast with three grid views. The top-left one has every even column shrunk by GridView API. Every grid view has a second column extended by EntryFrp API.
https://user-images.githubusercontent.com/6566674/185060985-7b7df076-c659-41fa-977a-22875493f8d4.mp4
**Note**: This PR also contains content of previous Grid View PR. We decided to discard the previous, because this one did some refactoring of old one, and it's not a big addition.
Added a scrollable::GridView component, which just embeds the GridView in ScrollArea. Also, re-worked the idea of text layers.
https://user-images.githubusercontent.com/3919101/179020359-512ee127-c333-4f86-bff5-f1cb4154e03c.mp4
