Add plugins search results: the plugin details modal opens in the thickbox modal

[afercia]

To reproduce:

• go in Plugins > Add New
• open a plugin details modal, for example from the "Featured" tab, click on the BuddyPress "More details" link
• the modal opens in the custom WordPress modal:

• now go in the Search tab and search for "buddypress"
• click on the BuddyPress "More details" link
• the modal opens in the default thickbox modal:

Worth noting the default thickbox modal doesn't handle well some accessibility requirements, for example tabbing is not constrained within the modal and Escape to close the modal works only in the modal top toolbar.

Seems to me this worked correctly in 4.8 and was introduced at some point in 4.9.

[afercia]

Seems to me this is a consequence of [41356]. The "custom modal" (which basically is some JS and CSS overriding) now kicks in only for modals with a plugin-details-modal CSS class, which in turn gets added only when clicking on the "More Details" link.
Worth noting the click event attached to the More Details link hasn't really ever worked in the Search results because the AJAX search rebuilds the HTML. Instead of attaching the event directly on the links, the event needs to be delegated.

[afercia]

In 42443:

Plugins: Fix the plugin details modal in the install plugin search tab after [41356].

Fixes #43082

[afercia]

Reopening for 4.9.2 consideration.

[SergeyBiryukov]

In 42456:

Plugins: Fix the plugin details modal in the install plugin search tab after [41356].

Props afercia.
Merges [42443] to the 4.9 branch.
Fixes #43082.

[afercia]

As reported by @rinkuyadav999 ​on Slack this broke the modal "Close" button. Quoting from the jQuery documentation:

​https://api.jquery.com/event.stoppropagation/

Since the .live() method handles events once they have propagated to the top of the document, it is not possible to stop propagation of live events. Similarly, events handled by .delegate() will propagate to the elements to which they are delegated; event handlers bound on any elements below it in the DOM tree will already have been executed by the time the delegated event handler is called. These handlers, therefore, may prevent the delegated handler from triggering by calling event.stopPropagation() or returning false.

Thus, this event still needs to be delegated but preferably on the closest available ancestor, to avoid conflicts with other handlers.

[afercia]

43082.2.diff​ delegates the event on the closest ancestor. To test:

• before applying the patch, open a plugin details modal
• click on the X "close" button on the top right
• verify the modal doesn't close
• apply the patch
• repeat the above steps
• verify the modal closes correctly

[afercia]

In 42491:

Plugins: Fix the plugin details modal "Close" button after [42443].

Props rinkuyadav999.
Fixes #43082.

[afercia]

Reopening (again) for 4.9.2 consideration :)

[SergeyBiryukov]

In 42493:

Plugins: Fix the plugin details modal "Close" button after [42443].

Props rinkuyadav999.
Merges [42491] to the 4.9 branch.
Fixes #43082.