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

base/win/event_trace_provider.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.
 //
 // Declaration of a Windows event trace provider class, to allow using
 // Windows Event Tracing for logging transport and control.
 #ifndef BASE_WIN_EVENT_TRACE_PROVIDER_H_
 #define BASE_WIN_EVENT_TRACE_PROVIDER_H_
 
 #include <windows.h>
@@ skipping 49 matching lines @@
               EtwEventVersion version, EtwEventLevel level) {
     memset(static_cast<Super*>(this), 0, sizeof(Super));
     header.Size = sizeof(Super);
     header.Guid = event_class;
     header.Class.Type = type;
     header.Class.Version = version;
     header.Class.Level = level;
     header.Flags = WNODE_FLAG_TRACED_GUID | WNODE_FLAG_USE_MOF_PTR;
   }
 
-  void SetField(int field, size_t size, const void *data) {
+  void SetField(size_t field, size_t size, const void* data) {
     // DCHECK(field < N);
     if ((field < N) && (size <= std::numeric_limits<uint32_t>::max())) {
       fields[field].DataPtr = reinterpret_cast<ULONG64>(data);
       fields[field].Length = static_cast<ULONG>(size);
     }
   }
 
   EVENT_TRACE_HEADER* get() { return& header; }
 
  private:
@@ skipping 93 matching lines @@
   // RegisterTraceGuids. Non-const, because that's how the API needs it.
   static TRACE_GUID_REGISTRATION obligatory_guid_registration_;
 
   DISALLOW_COPY_AND_ASSIGN(EtwTraceProvider);
 };
 
 }  // namespace win
 }  // namespace base
 
 #endif  // BASE_WIN_EVENT_TRACE_PROVIDER_H_