Fix more disabled MSVC warnings, base/ edition.

base/logging.cc

 // Copyright (c) 2012 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/logging.h"
 
 #if defined(OS_WIN)
 #include <io.h>
 #include <windows.h>
 typedef HANDLE FileHandle;
@@ skipping 669 matching lines @@
   }
   if (log_tickcount)
     stream_ << TickCount() << ':';
   if (severity_ >= 0)
     stream_ << log_severity_name(severity_);
   else
     stream_ << "VERBOSE" << -severity_;
 
   stream_ << ":" << filename << "(" << line << ")] ";
 
-  message_start_ = stream_.tellp();
+  message_start_ = stream_.str().length();
 }
 
 #if defined(OS_WIN)
 // This has already been defined in the header, but defining it again as DWORD
 // ensures that the type used in the header is equivalent to DWORD. If not,
 // the redefinition is a compile error.
 typedef DWORD SystemErrorCode;
 #endif
 
 SystemErrorCode GetLastSystemErrorCode() {
@@ skipping 105 matching lines @@
     return *log_file_name;
   return std::wstring();
 }
 #endif
 
 }  // namespace logging
 
 std::ostream& std::operator<<(std::ostream& out, const wchar_t* wstr) {
   return out << base::WideToUTF8(std::wstring(wstr));
 }