Fix and improve styling for links in the datagrids.

Review Request #9080 — Created July 15, 2017 and submitted


Our datagrids were rendering with extra, unwanted <a> tags for some
columns. Part of this was due to an old change that regressed the
link=False semantics, causing this flag to just result in link_func
being ignored rather than disabling linking. Another part was due to the
usage of <div> within <a>, which isn't legal and caused the browser
to do odd things that easily resulted in duplicate tags. Still another
was the need for rendering custom <a> tags as part of the cell data
when in need of a custom CSS class (which often resulted in extra tags
given the link=False breakage).

Now, link=False is respected. When provided, links will not be
generated for the row's object in the data automatically. Similarly, if
link_func fails, the URL won't fall back to the URL for the row's

The <a> tags no longer contain a <div>. Instead, we just assign
display: block to the <a>. The cell also gained a has-link CSS
class to help with styling, so that there's no impact on custom <a>
tags within the cell.

Columns can now accept a link_css_class attribute, which specifies the
CSS class names (or a function returning them) to apply to the <a>,
reducing the work that a column has to do and reducing the amount of
data that must be cached.

This shouldn't outright break any consumers unless they're using
link=False and still expecting links to show up (which wasn't really
ever the intended behavior). However, they can now take advantage of
link_css_class to reduce the data they must render.

Tested with Review Board, both the current upstream and with a change
that takes advantage of the new link_css_class.

  1. Ship It!
Review request changed

Status: Closed (submitted)

Change Summary:

Pushed to release-0.10.x (06741b9)