clang/win: Let some chromium_code targets build with -Wextra.

sandbox/win/src/sandbox_policy_base.h

 // 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.
 
 #ifndef SANDBOX_WIN_SRC_SANDBOX_POLICY_BASE_H_
 #define SANDBOX_WIN_SRC_SANDBOX_POLICY_BASE_H_
 
 #include <windows.h>
 
 #include <list>
@@ skipping 72 matching lines @@
 
   // Creates the two tokens with the levels specified in a previous call to
   // SetTokenLevel(). Also creates a lowbox token if specified based on the
   // lowbox SID.
   ResultCode MakeTokens(base::win::ScopedHandle* initial,
                         base::win::ScopedHandle* lockdown,
                         base::win::ScopedHandle* lowbox);
 
   const AppContainerAttributes* GetAppContainer() const;
 
-  const PSID GetLowBoxSid() const;
+  PSID GetLowBoxSid() const;
 
   // Adds a target process to the internal list of targets. Internally a
   // call to TargetProcess::Init() is issued.
   bool AddTarget(TargetProcess* target);
 
   // Called when there are no more active processes in a Job.
   // Removes a Job object associated with this policy and the target associated
   // with the job.
   bool OnJobEmpty(HANDLE job);
 
@@ skipping 77 matching lines @@
   // This list contains handles other than the stderr/stdout handles which are
   // shared with the target at times.
   HandleList handles_to_share_;
 
   DISALLOW_COPY_AND_ASSIGN(PolicyBase);
 };
 
 }  // namespace sandbox
 
 #endif  // SANDBOX_WIN_SRC_SANDBOX_POLICY_BASE_H_