rustdoc: change title of search results

the current title is too similar to that of the page for
std::result::Result, which is a problem both for
navigating to the Result docs via browser autocomplete, and for
being able to tell which tab is which when the width of tabs is
small.

src/librustdoc/html/static/js/search.js

@@ -2932,7 +2932,7 @@ ${item.displayPath}<span class="${type}">${name}</span>\
         }
 
         // Update document title to maintain a meaningful browser history
-        searchState.title = "Results for " + query.original + " - Rust";
+        searchState.title = '"' + query.original + '" Search - Rust';
 
         // Because searching is incremental by character, only the most
         // recent search query is added to the browser history.