Add Locking calls to file_io.h plus implementations and test

util/test/errors.cc

 // Copyright 2014 The Crashpad Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 //     http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
 #include "util/test/errors.h"
 
 #include <errno.h>
 
+#include "base/logging.h"
+#include "base/strings/stringprintf.h"
 #include "build/build_config.h"
-#include "base/strings/stringprintf.h"
 
 #if defined(OS_POSIX)
 #include "base/safe_strerror_posix.h"
 #elif defined(OS_WIN)
 #include <string.h>
+#include <windows.h>
 #endif
 
 namespace crashpad {
 namespace test {
 
 std::string ErrnoMessage(int err, const std::string& base) {
 #if defined(OS_POSIX)
   std::string err_as_string = safe_strerror(errno);
   const char* err_string = err_as_string.c_str();
 #elif defined(OS_WIN)
   char err_string[256];
   strerror_s(err_string, errno);
 #endif
   return base::StringPrintf("%s%s%s (%d)",
                             base.c_str(),
                             base.empty() ? "" : ": ",
                             err_string,
                             err);
 }
 
 std::string ErrnoMessage(const std::string& base) {
   return ErrnoMessage(errno, base);
 }
 
+#if defined(OS_WIN)
+std::string ErrorMessage(const std::string& base) {
+  return base::StringPrintf(
+      "%s%s%s",
+      base.c_str(),
+      base.empty() ? "" : ": ",
+      logging::SystemErrorCodeToString(GetLastError()).c_str());
+}
+#endif
+
 }  // namespace test
 }  // namespace crashpad