[fsp] Add an option for mounting in R/W mode.

chrome/browser/chromeos/file_system_provider/fileapi/file_stream_reader_unittest.cc

 // Copyright 2014 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 "chrome/browser/chromeos/file_system_provider/fileapi/file_stream_reader.h"
 
 #include <string>
 #include <vector>
 
 #include "base/files/file.h"
@@ skipping 78 matching lines @@
     profile_manager_.reset(
         new TestingProfileManager(TestingBrowserProcess::GetGlobal()));
     ASSERT_TRUE(profile_manager_->SetUp());
     profile_ = profile_manager_->CreateTestingProfile("testing-profile");
 
     ServiceFactory::GetInstance()->SetTestingFactory(profile_, &CreateService);
     Service* service = Service::Get(profile_);  // Owned by its factory.
     service->SetFileSystemFactoryForTesting(
         base::Bind(&FakeProvidedFileSystem::Create));
 
-    const bool result = service->MountFileSystem(
-        kExtensionId, kFileSystemId, "Testing File System");
+    const bool result = service->MountFileSystem(kExtensionId,
+                                                 kFileSystemId,
+                                                 "Testing File System",
+                                                 false /* writable */);
     ASSERT_TRUE(result);
     const ProvidedFileSystemInfo& file_system_info =
         service->GetProvidedFileSystem(kExtensionId, kFileSystemId)
             ->GetFileSystemInfo();
     const std::string mount_point_name =
         file_system_info.mount_path().BaseName().AsUTF8Unsafe();
 
     file_url_ = CreateFileSystemURL(
         mount_point_name, base::FilePath::FromUTF8Unsafe(kFakeFilePath + 1));
     ASSERT_TRUE(file_url_.is_valid());
@@ skipping 238 matching lines @@
   EXPECT_EQ(net::ERR_IO_PENDING, result);
   base::RunLoop().RunUntilIdle();
 
   ASSERT_EQ(1u, logger.results().size());
   EXPECT_LT(0, logger.results()[0]);
   EXPECT_EQ(kFakeFileSize, static_cast<size_t>(logger.results()[0]));
 }
 
 }  // namespace file_system_provider
 }  // namespace chromeos