rustdoc: hide modals when resizing the sidebar

Follow-up for
#119477 (comment)

src/librustdoc/html/static/js/main.js

@@ -1721,6 +1721,7 @@ href="https://doc.rust-lang.org/${channel}/rustdoc/read-documentation/search.htm
             }
             currentPointerId = e.pointerId;
         }
+        window.hideAllModals(false);
         e.preventDefault();
         window.addEventListener("pointermove", resize, false);
         window.addEventListener("pointercancel", stopResize, false);

tests/rustdoc-gui/sidebar-resize-close-popover.goml

@@ -0,0 +1,20 @@
+// Checks sidebar resizing close the Settings popover
+go-to: "file://" + |DOC_PATH| + "/test_docs/index.html"
+assert-property: (".sidebar", {"clientWidth": "200"})
+show-text: true
+click: "#settings-menu"
+wait-for: "#settings"
+assert-css: ("#settings", {"display": "block"})
+// normal resizing
+drag-and-drop: ((205, 100), (185, 100))
+assert-property: (".sidebar", {"clientWidth": "182"})
+assert-css: ("#settings", {"display": "none"})
+
+// Now same thing, but for source code
+go-to: "file://" + |DOC_PATH| + "/src/test_docs/lib.rs.html"
+click: "#settings-menu"
+wait-for: "#settings"
+assert-css: ("#settings", {"display": "block"})
+assert-property: (".sidebar", {"clientWidth": "49"})
+drag-and-drop: ((52, 100), (185, 100))
+assert-css: ("#settings", {"display": "none"})