Components: Prevent <Search> from stealing the focus when typing elsewhere

[nylen]

This fixes #1389 where if the location field has user-entered text, it steals the focus back when typing into another text field:

I'm not seeing a good reason why we would want the <Search> component to focus itself if it has text: in any such situation, shouldn't it already be focused?

This code or some variation of it has been present since long before OSS release. As far as I can tell, these are the conditions needed for the bug to surface:

• A <Search> and another text field both present on the same screen
• A structure that causes componentDidUpdate to be called when the other text field changes (in the editor, this is the case, but I'm not entirely sure why)

@aduth @mtias I saw your names a lot in the history of this component, want to take a look?

[rralian]

I'm not positive, but I think this had to do with search pages that append the search query as a url parameter (e.g., posts: /posts/example.wordpress.com?s=test). What happens on those pages is that we update the url, which triggers the controller, which then passes the parameter back into the search box. I think at the time that process must have caused the search field to lose focus. It's not doing so now though from my testing. So I'm not aware of any reason we need this. Would welcome a second opinion though.

[mtias]

It's not doing so now though from my testing.

In my testing, loading a page with the s=test query doesn't focus the search input, not in this PR but neither in master.

[mtias]

@nylen this seems like a good change, I can't figure out why we had that piece of code, it doesn't seem to be doing anything productive, and simpler code is always welcome :)

If someone wanted to focus the main search in a page based on the query string it seems to me they should be explicit about it and set the autoFocus prop based on the query string.

[rralian]

In my testing, loading a page with the s=test query doesn't focus the search input, not in this PR but neither in master.

I'm not positive that's functionally equivalent to typing in the text field. Anyway, I can't account for a reason for this code right now and so I support removing it. This code became really complex, so could use some simplification and refactoring in general. For example, it aint great that we aren't sure why/whether this clause was ever needed.

[nylen]

If someone wanted to focus the main search in a page based on the query string it seems to me they should be explicit about it and set the autoFocus prop based on the query string.

Agreed

it aint great that we aren't sure why/whether this clause was ever needed

and agreed :0