[Launcher settings] Add accessible names for search results.

Settings results aren't distinguishable from other results when used
with a screen reader. This CL manually sets their accessible name, and
includes the name of the settings app at the end to mark them.

Settings results are read as, for example:

  "Powerwash, reset settings, settings"

This is consistent with other results' a11y names, which have a
"result, category" pattern.

Bug: 1068851
Change-Id: I24e12e21c05d43bcc99ab89c34a5b508d0f6fff4
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2237563Reviewed-by: Thanh Nguyen <thanhdng@chromium.org>
Commit-Queue: Tony Yeoman <tby@chromium.org>
Cr-Commit-Position: refs/heads/master@{#777256}

chrome/browser/ui/app_list/search/os_settings_provider.cc

@@ -134,6 +134,20 @@ OsSettingsResult::OsSettingsResult(
   } else if (result->type != SettingsResultType::kSection) {
     SetDetails(hierarchy.back());
   }
+
+  // Manually build the accessible name for the search result, in a way that
+  // parallels the regular accessible names set by
+  // SearchResultBaseView::ComputeAccessibleName.
+  base::string16 accessible_name = title();
+  if (!details().empty()) {
+    accessible_name += base::ASCIIToUTF16(", ");
+    accessible_name += details();
+  }
+  accessible_name += base::ASCIIToUTF16(", ");
+  // The first element in the settings hierarchy is always the top-level
+  // localized name of the Settings app.
+  accessible_name += hierarchy[0];
+  SetAccessibleName(accessible_name);
 }
 
 OsSettingsResult::~OsSettingsResult() = default;