Add test to check that font-weight is correctly set on type page

Author: GuillaumeGomez

src/test/rustdoc-gui/sidebar.goml

@@ -11,7 +11,8 @@ assert: (".sidebar-elems > .items > ul > li:nth-child(2)", "Structs")
 assert: (".sidebar-elems > .items > ul > li:nth-child(3)", "Enums")
 assert: (".sidebar-elems > .items > ul > li:nth-child(4)", "Traits")
 assert: (".sidebar-elems > .items > ul > li:nth-child(5)", "Functions")
-assert: (".sidebar-elems > .items > ul > li:nth-child(6)", "Keywords")
+assert: (".sidebar-elems > .items > ul > li:nth-child(6)", "Type Definitions")
+assert: (".sidebar-elems > .items > ul > li:nth-child(7)", "Keywords")
 assert: ("#structs + table td > a", "Foo")
 click: "#structs + table td > a"
 

src/test/rustdoc-gui/src/lib.rs

@@ -96,3 +96,6 @@ pub enum AnEnum {
 
 #[doc(keyword = "CookieMonster")]
 pub mod keyword {}
+
+/// Just some type alias.
+pub type SomeType = u32;

src/test/rustdoc-gui/type-weight.rs

@@ -0,0 +1,2 @@
+goto: file://|DOC_PATH|/test_docs/type.SomeType.html
+assert-all: (".top-block .docblock p", {"font-weight": "400"})