Reland "Fix various issues in RedirectToFileResourceHandler."

It got reverted due to ASan issues. Fix child_id registration in
ResourceDispatcherHostTests so that they happen on ForwardingFilter creation,
rather than ad-hoc on a per-request basis.

Original description:

> - Handle errors in creating temporary files.
> - Cancel on write failure instead of resuming. This used to work, but got
>   lost in some refactoring in r142108.
> - Fix the OnResponseCompleted resume logic to account for partial writes.
> - Don't lose write errors which occur after OnResponseCompleted is received.
> - WeakPtrFactory goes after other members.
> - OnWillStart was never forwarded to downstream handlers.
> - Make sure the file is closed before deleting it.
>
> Also add a lot of machinery so we can better unit test this stack.

Original Review URL: https://codereview.chromium.org/82273002

BUG=316634,347663
TEST=ResourceDispatcherHostTest.DownloadToFile
     ResourceDispatcherHostTest.RegisterDownloadedTempFile
     ResourceLoaderRedirectToFileTest.*
     TemporaryFileStreamTest.Basic

Review URL: https://codereview.chromium.org/199453002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@257147 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 46 insertions, 0 deletions

diff --git a/content/browser/loader/temporary_file_stream.h b/content/browser/loader/temporary_file_stream.h
new file mode 100644
index 0000000..51d524d
--- /dev/null
+++ b/content/browser/loader/temporary_file_stream.h
@@ -0,0 +1,46 @@
+// 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.
+
+#ifndef CONTENT_BROWSER_LOADER_TEMPORARY_FILE_STREAM_H_
+#define CONTENT_BROWSER_LOADER_TEMPORARY_FILE_STREAM_H_
+
+#include "base/callback_forward.h"
+#include "base/files/file.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/platform_file.h"
+#include "content/common/content_export.h"
+
+namespace net {
+class FileStream;
+}
+
+namespace webkit_blob {
+class ShareableFileReference;
+}
+
+namespace content {
+
+typedef base::Callback<void(base::File::Error,
+                            scoped_ptr<net::FileStream>,
+                            webkit_blob::ShareableFileReference*)>
+    CreateTemporaryFileStreamCallback;
+
+// Creates a temporary file and asynchronously calls |callback| with a
+// net::FileStream and webkit_blob::ShareableFileReference. The file is deleted
+// when the webkit_blob::ShareableFileReference is deleted. Note it is the
+// consumer's responsibility to ensure the webkit_blob::ShareableFileReference
+// stays in scope until net::FileStream has finished closing the file. On error,
+// |callback| is called with an error in the first parameter.
+//
+// This function may only be called on the IO thread.
+//
+// TODO(davidben): Juggling the net::FileStream and
+// webkit_blob::ShareableFileReference lifetimes is a nuisance. The two should
+// be tied together so the consumer need not deal with it.
+CONTENT_EXPORT void CreateTemporaryFileStream(
+    const CreateTemporaryFileStreamCallback& callback);
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_LOADER_TEMPORARY_FILE_STREAM_H_