[ios] Adds contextual_search and omnibox resources

ios/chrome/browser/ui/contextual_search/BUILD.gn

Index: ios/chrome/browser/ui/contextual_search/BUILD.gn
diff --git a/ios/chrome/browser/ui/contextual_search/BUILD.gn b/ios/chrome/browser/ui/contextual_search/BUILD.gn
new file mode 100644
index 0000000000000000000000000000000000000000..3ec61b2d015309c2d51495e0f73104fce94049ae
--- /dev/null
+++ b/ios/chrome/browser/ui/contextual_search/BUILD.gn
@@ -0,0 +1,14 @@
+# Copyright 2016 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+bundle_data("resources") {
+  sources = [
+    "resources/expand_less.png",
+    "resources/expand_less@2x.png",
+    "resources/expand_less@3x.png",
+  ]
+  outputs = [
+    "{{bundle_resources_dir}}/{{source_file_part}}",
+  ]
+}