Replace wstring with string16 in sandbox

sandbox/win/src/process_thread_dispatcher.h

Index: sandbox/win/src/process_thread_dispatcher.h
diff --git a/sandbox/win/src/process_thread_dispatcher.h b/sandbox/win/src/process_thread_dispatcher.h
index 1cc5743998f3fa8d06e46acad0b26bf583207ab3..fba27541b3247c3080b1b588a8f38c0e1f928e54 100644
--- a/sandbox/win/src/process_thread_dispatcher.h
+++ b/sandbox/win/src/process_thread_dispatcher.h
@@ -6,6 +6,7 @@
 #define SANDBOX_SRC_PROCESS_THREAD_DISPATCHER_H_
 
 #include "base/basictypes.h"
+#include "base/strings/string16.h"
 #include "sandbox/win/src/crosscall_server.h"
 #include "sandbox/win/src/sandbox_policy_base.h"
 
@@ -35,8 +36,11 @@ class ThreadProcessDispatcher : public Dispatcher {
                             DWORD attributes);
 
   // Processes IPC requests coming from calls to CreateProcessW() in the target.
-  bool CreateProcessW(IPCInfo* ipc, std::wstring* name, std::wstring* cmd_line,
-                      std::wstring* cur_dir, CountedBuffer* info);
+  bool CreateProcessW(IPCInfo* ipc,
+                      base::string16* name,
+                      base::string16* cmd_line,
+                      base::string16* cur_dir,
+                      CountedBuffer* info);
 
   PolicyBase* policy_base_;
   DISALLOW_COPY_AND_ASSIGN(ThreadProcessDispatcher);