Rollup merge of #99810 - GuillaumeGomez:fix-settings-slider-small-width, r=notriddle

Fix settings slider on small width screens

Fixes #99794.

Screenshot of the fix:

![Screenshot from 2022-07-27 14-17-08](https://user-images.githubusercontent.com/3050060/181250007-55f982d1-89db-45b7-a4f1-0d1729e6a3e3.png)

cc `````@jsha`````
r? `````@notriddle`````

src/librustdoc/html/static/css/settings.css

@@ -41,9 +41,7 @@
 
 .toggle {
 	position: relative;
-	display: inline-block;
 	width: 100%;
-	height: 27px;
 	margin-right: 20px;
 	display: flex;
 	align-items: center;
@@ -58,6 +56,7 @@
 .slider {
 	position: relative;
 	width: 45px;
+	min-width: 45px;
 	display: block;
 	height: 28px;
 	margin-right: 20px;

src/test/rustdoc-gui/settings.goml

@@ -147,3 +147,12 @@ assert-false: "noscript section"
 javascript: false
 reload:
 assert-css: ("noscript section", {"display": "block"})
+javascript: true
+
+// Check for the display on small screen
+show-text: true
+reload:
+size: (300, 1000)
+click: "#settings-menu"
+wait-for: "#settings"
+assert-css: ("#settings .slider", {"width": "45px"}, ALL)