Auto merge of #53577 - GuillaumeGomez:rustdoc-substring-search, r=QuietMisdreavus

Search a substring instead of start of string in rustdoc search

Fixes #49762.

r? @QuietMisdreavus

src/test/rustdoc-js/substring.js

@@ -0,0 +1,20 @@
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// exact-check
+
+const QUERY = 'waker_from';
+
+const EXPECTED = {
+    'others': [
+        { 'path': 'std::task', 'name': 'local_waker_from_nonlocal' },
+        { 'path': 'alloc::task', 'name': 'local_waker_from_nonlocal' },
+    ],
+};