rustdoc: Style of [src] link for trait implementors

A change suggested by @GuillaumeGomez and @QuietMisdreavus.

Also slight reindenting of the appropriate CSS section.

src/librustdoc/html/static/rustdoc.css

@@ -111,7 +111,10 @@ h3.impl, h3.method, h4.method, h3.type, h4.type, h4.associatedconstant {
 h3.impl, h3.method, h3.type {
 	margin-top: 15px;
 }
-h1, h2, h3, h4, .sidebar, a.source, .search-input, .content table :not(code)>a, .collapse-toggle {
+
+h1, h2, h3, h4,
+.sidebar, a.source, .search-input, .content table :not(code)>a,
+.collapse-toggle, ul.item-list > li > .out-of-band {
 	font-family: "Fira Sans", "Helvetica Neue", Helvetica, Arial, sans-serif;
 }
 
@@ -310,6 +313,10 @@ h4.method > .out-of-band {
 	font-size: 19px;
 }
 
+ul.item-list > li > .out-of-band {
+	font-size: 19px;
+}
+
 h4 > code, h3 > code, .invisible > code {
 	position: inherit;
 }