2 files changed, 17 insertions, 2 deletions
diff --git a/base/string_util.cc b/base/string_util.cc
index a13f79f..8f9bcf9 100644
--- a/base/string_util.cc
+++ b/base/string_util.cc
@@ -27,6 +27,16 @@
 
 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.
@@ -323,11 +333,15 @@ bool IsWprintfFormatPortable(const wchar_t* format) {
 
 
 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[] = {
diff --git a/base/string_util.h b/base/string_util.h
index 1247cd5..3f905fe 100644
--- a/base/string_util.h
+++ b/base/string_util.h
@@ -112,6 +112,7 @@ bool IsWprintfFormatPortable(const wchar_t* format);
 // These functions are threadsafe.
 const std::string& EmptyString();
 const std::wstring& EmptyWString();
+const string16& EmptyString16();
 
 extern const wchar_t kWhitespaceWide[];
 extern const char kWhitespaceASCII[];