Fix license headers in a number of files

base/base64_unittest.cc

-// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
+// Copyright (c) 2012 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 "base/base64.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace {
 
 class Base64Test : public testing::Test {
 };
 
 }  // namespace
 
 TEST(Base64Test, Basic) {
   const std::string kText = "hello world";
   const std::string kBase64Text = "aGVsbG8gd29ybGQ=";
 
   std::string encoded, decoded;
   bool ok;
 
   ok = base::Base64Encode(kText, &encoded);
   EXPECT_TRUE(ok);
   EXPECT_EQ(kBase64Text, encoded);
 
   ok = base::Base64Decode(encoded, &decoded);
   EXPECT_TRUE(ok);
   EXPECT_EQ(kText, decoded);
 }