Update some uses of UTF conversions in chrome/browser to use the base:: namespace.

chrome/browser/ui/gtk/bookmarks/bookmark_utils_gtk_unittest.cc

 // Copyright (c) 2011 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.
 
 #include "chrome/browser/ui/gtk/bookmarks/bookmark_utils_gtk.h"
 
 #include <string>
 
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/bookmarks/bookmark_model.h"
@@ skipping 25 matching lines @@
   guchar test_data[] = "";
   data.data = test_data;
   data.length = 0;
   nodes = GetNodesFromSelection(
       NULL, &data, ui::CHROME_BOOKMARK_ITEM, NULL, NULL, NULL);
   EXPECT_EQ(0u, nodes.size());
 }
 
 TEST(BookmarkUtilsGtkTest, WriteBookmarkToSelectionHTML) {
   BookmarkNode x(GURL("http://www.google.com"));
-  x.SetTitle(base::string16(ASCIIToUTF16("Google")));
+  x.SetTitle(base::string16(base::ASCIIToUTF16("Google")));
   GtkSelectionData data;
   data.data = NULL;
   data.length = 0;
   WriteBookmarkToSelection(&x, &data, ui::TEXT_HTML, NULL);
   std::string selection(reinterpret_cast<char*>(data.data), data.length);
   EXPECT_EQ("<a href=\"http://www.google.com/\">Google</a>", selection);
 
   // Free the copied data in GtkSelectionData
   gtk_selection_data_set(&data, data.type, data.format, NULL, -1);
 }