Convert NavigationEntry title to string16. TabContents::GetTitle no longer ne...

base/string_util.cc

 // Copyright (c) 2006-2008 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/string_util.h"
 
 #include "build/build_config.h"
 
 #include <ctype.h>
 #include <errno.h>
 #include <math.h>
 #include <stdarg.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <time.h>
 #include <wchar.h>
 #include <wctype.h>
 
 #include <algorithm>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/logging.h"
 #include "base/singleton.h"
 #include "base/third_party/dmg_fp/dmg_fp.h"
 
 namespace {
 
+// Force the singleton used by Empty[W]String[16] to be a unique type. This
+// prevents other code that might accidentally use Singleton<string> from
+// getting our internal one.
+struct EmptyStrings {
+  EmptyStrings() {}
+  const std::string s;
+  const std::wstring ws;
+  const string16 s16;
+};
+
 // Hack to convert any char-like type to its unsigned counterpart.
 // For example, it will convert char, signed char and unsigned char to unsigned
 // char.
 template<typename T>
 struct ToUnsigned {
   typedef T Unsigned;
 };
 
 template<>
 struct ToUnsigned<char> {
@@ skipping 276 matching lines @@
   }
 
   return true;
 }
 
 
 }  // namespace base
 
 
 const std::string& EmptyString() {
-  return *Singleton<std::string>::get();
+  return Singleton<EmptyStrings>::get()->s;
 }
 
 const std::wstring& EmptyWString() {
-  return *Singleton<std::wstring>::get();
+  return Singleton<EmptyStrings>::get()->ws;
+}
+
+const string16& EmptyString16() {
+  return Singleton<EmptyStrings>::get()->s16;
 }
 
 const wchar_t kWhitespaceWide[] = {
   0x0009,  // <control-0009> to <control-000D>
   0x000A,
   0x000B,
   0x000C,
   0x000D,
   0x0020,  // Space
   0x0085,  // <control-0085>
@@ skipping 1313 matching lines @@
   // Each input byte creates two output hex characters.
   std::string ret(size * 2, '\0');
 
   for (size_t i = 0; i < size; ++i) {
     char b = reinterpret_cast<const char*>(bytes)[i];
     ret[(i * 2)] = kHexChars[(b >> 4) & 0xf];
     ret[(i * 2) + 1] = kHexChars[b & 0xf];
   }
   return ret;
 }