search-result: Use a larger icon size

Increase the icon size of search results for consistency with the
application view. To account for the larger icons, only display
a single row of results per section.

https://bugzilla.gnome.org/show_bug.cgi?id=643632

js/ui/searchDisplay.js

@@ -13,7 +13,7 @@ const Main = imports.ui.main;
 const Overview = imports.ui.overview;
 const Search = imports.ui.search;
 
-const MAX_SEARCH_RESULTS_ROWS = 2;
+const MAX_SEARCH_RESULTS_ROWS = 1;
 
 
 function SearchResult(provider, metaInfo, terms) {