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

chrome/browser/spellchecker/word_trimmer_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/spellchecker/word_trimmer.h"
 
 #include "base/strings/utf_string_conversions.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
+using base::ASCIIToUTF16;
+
 TEST(WordTrimmerTest, TrimWordsEmptyText) {
   size_t start = 0;
   size_t end = 0;
   EXPECT_EQ(base::string16(), TrimWords(&start, end, base::string16(), 0));
   EXPECT_EQ(0UL, start);
 }
 
 TEST(WordTrimmerTest, TrimWordsStart) {
   size_t start = 0;
   size_t end = 3;
@@ skipping 34 matching lines @@
   EXPECT_EQ(4UL, start);
 }
 
 TEST(WordTrimmerTest, TrimWordsInvalid) {
   size_t start = 23;
   size_t end = 14;
   EXPECT_EQ(ASCIIToUTF16("one two three four five six seven eight"), TrimWords(
       &start, end, ASCIIToUTF16("one two three four five six seven eight"), 2));
   EXPECT_EQ(23UL, start);
 }