Rollup merge of #98776 - notriddle:notriddle/mobile-sidebar-auto-close, r=GuillaumeGomez

rustdoc: improve click behavior of the source code mobile full-screen "sidebar"

On desktop, if you open the source code sidebar, it stays open even when you move from page to page. It used to do the same thing on mobile, but I think that's stupid. Since the file list fills the entire screen on mobile, and you can't really do anything with the currently selected file other than dismiss the "sidebar" to look at it, it's safe to assume that anybody who clicks a file in that list probably wants the list to go away so they can see it.

Split out separately from #98772

src/librustdoc/html/static/css/rustdoc.css

@@ -1739,6 +1739,11 @@ details.rustdoc-toggle[open] > summary.hideme::after {
 
 /* Media Queries */
 
+/*
+WARNING: RUSTDOC_MOBILE_BREAKPOINT MEDIA QUERY;
+If you update this line, then you also need to update the line with the same warning
+in storage.js plus the media query with (max-width: 700px)
+*/
 @media (min-width: 701px) {
 	/* In case there is no documentation before a code block, we need to add some margin at the top
 	to prevent an overlay between the "collapse toggle" and the information tooltip.
@@ -1759,6 +1764,11 @@ details.rustdoc-toggle[open] > summary.hideme::after {
 	}
 }
 
+/*
+WARNING: RUSTDOC_MOBILE_BREAKPOINT MEDIA QUERY
+If you update this line, then you also need to update the line with the same warning
+in storage.js plus the media query with (min-width: 701px)
+*/
 @media (max-width: 700px) {
 	/* When linking to an item with an `id` (for instance, by clicking a link in the sidebar,
 	   or visiting a URL with a fragment like `#method.new`, we don't want the item to be obscured