Require FLAG_WRITE when FLAG_CREATE_ALWAYS is specified

base/platform_file_unittest.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/file_util.h"
 #include "base/files/scoped_temp_dir.h"
 #include "base/platform_file.h"
 #include "base/time/time.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
@@ skipping 83 matching lines @@
       &created,
       &error_code);
   EXPECT_EQ(kInvalidPlatformFileValue, file);
   EXPECT_FALSE(created);
   EXPECT_EQ(PLATFORM_FILE_ERROR_EXISTS, error_code);
 
   // Create or overwrite a file.
   error_code = PLATFORM_FILE_OK;
   file = CreatePlatformFile(
       file_path,
-      PLATFORM_FILE_CREATE_ALWAYS | PLATFORM_FILE_READ,
+      PLATFORM_FILE_CREATE_ALWAYS | PLATFORM_FILE_WRITE,
       &created,
       &error_code);
   EXPECT_NE(kInvalidPlatformFileValue, file);
   EXPECT_TRUE(created);
   EXPECT_EQ(PLATFORM_FILE_OK, error_code);
   ClosePlatformFile(file);
 
   // Create a delete-on-close file.
   created = false;
   file_path = temp_dir.path().AppendASCII("create_file_2");
@@ skipping 330 matching lines @@
             ReadPlatformFileAtCurrentPos(
                 file, buffer + first_chunk_size,
                 kDataSize - first_chunk_size));
   EXPECT_EQ(std::string(buffer, buffer + kDataSize),
             std::string(kData));
 
   ClosePlatformFile(file);
 }
 
 }  // namespace base