Migrate DevToolsFileSystemIndexer to base::FileProxy

chrome/browser/devtools/devtools_file_system_indexer.cc

Index: chrome/browser/devtools/devtools_file_system_indexer.cc
diff --git a/chrome/browser/devtools/devtools_file_system_indexer.cc b/chrome/browser/devtools/devtools_file_system_indexer.cc
index 9a281db855c615623c936319eb8a2d27c6ea1522..7e0d6fcbd04b67273fbce0939f3d9d363758a76a 100644
--- a/chrome/browser/devtools/devtools_file_system_indexer.cc
+++ b/chrome/browser/devtools/devtools_file_system_indexer.cc
@@ -21,7 +21,6 @@ using base::Bind;
 using base::Callback;
 using base::FileEnumerator;
 using base::FilePath;
-using base::FileUtilProxy;
 using base::Time;
 using base::TimeDelta;
 using base::TimeTicks;
@@ -269,6 +268,8 @@ DevToolsFileSystemIndexer::FileSystemIndexingJob::FileSystemIndexingJob(
       total_work_callback_(total_work_callback),
       worked_callback_(worked_callback),
       done_callback_(done_callback),
+      current_file_(BrowserThread::GetMessageLoopProxyForThread(
+                        BrowserThread::FILE).get()),
       files_indexed_(0),
       stopped_(false) {
   current_trigrams_set_.resize(kTrigramCount);
@@ -337,23 +338,18 @@ void DevToolsFileSystemIndexer::FileSystemIndexingJob::IndexFiles() {
     return;
   }
   FilePath file_path = indexing_it_->first;
-  FileUtilProxy::CreateOrOpen(
-      BrowserThread::GetMessageLoopProxyForThread(BrowserThread::FILE).get(),
-      file_path,
-      base::PLATFORM_FILE_OPEN | base::PLATFORM_FILE_READ,
-      Bind(&FileSystemIndexingJob::StartFileIndexing, this));
+  current_file_.CreateOrOpen(
+        file_path,
+        base::File::FLAG_OPEN | base::File::FLAG_READ,
+        Bind(&FileSystemIndexingJob::StartFileIndexing, this));
 }
 
 void DevToolsFileSystemIndexer::FileSystemIndexingJob::StartFileIndexing(
-    base::File::Error error,
-    PassPlatformFile pass_file,
-    bool) {
-  if (error != base::File::FILE_OK) {
-    current_file_ = base::kInvalidPlatformFileValue;
+    base::File::Error error) {
+  if (!current_file_.IsValid()) {
     FinishFileIndexing(false);
     return;
   }
-  current_file_ = pass_file.ReleaseValue();
   current_file_offset_ = 0;
   current_trigrams_.clear();
   std::fill(current_trigrams_set_.begin(), current_trigrams_set_.end(), false);
@@ -365,12 +361,8 @@ void DevToolsFileSystemIndexer::FileSystemIndexingJob::ReadFromFile() {
     CloseFile();
     return;
   }
-  FileUtilProxy::Read(
-      BrowserThread::GetMessageLoopProxyForThread(BrowserThread::FILE).get(),
-      current_file_,
-      current_file_offset_,
-      kMaxReadLength,
-      Bind(&FileSystemIndexingJob::OnRead, this));
+  current_file_.Read(current_file_offset_, kMaxReadLength,
+                     Bind(&FileSystemIndexingJob::OnRead, this));
 }
 
 void DevToolsFileSystemIndexer::FileSystemIndexingJob::OnRead(
@@ -425,12 +417,8 @@ void DevToolsFileSystemIndexer::FileSystemIndexingJob::FinishFileIndexing(
 }
 
 void DevToolsFileSystemIndexer::FileSystemIndexingJob::CloseFile() {
-  if (current_file_ != base::kInvalidPlatformFileValue) {
-    FileUtilProxy::Close(
-        BrowserThread::GetMessageLoopProxyForThread(BrowserThread::FILE).get(),
-        current_file_,
-        Bind(&FileSystemIndexingJob::CloseCallback, this));
-  }
+  if (current_file_.IsValid())
+    current_file_.Close(Bind(&FileSystemIndexingJob::CloseCallback, this));
 }
 
 void DevToolsFileSystemIndexer::FileSystemIndexingJob::CloseCallback(