Declare providing extension capabilities in the manifest.

chrome/common/extensions/api/file_system_provider/file_system_provider_handler.h

+// Copyright 2015 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 CHROME_COMMON_EXTENSIONS_API_FILE_SYSTEM_PROVIDER_FILE_SYSTEM_PROVIDER_HANDLER_H_
+#define CHROME_COMMON_EXTENSIONS_API_FILE_SYSTEM_PROVIDER_FILE_SYSTEM_PROVIDER_HANDLER_H_
+
+#include <string>
+#include <vector>
+
+#include "chrome/common/extensions/api/file_system_provider.h"
+#include "extensions/common/extension.h"
+#include "extensions/common/manifest_handler.h"
+
+namespace extensions {
+
+// Source of provider file systems.
+enum FileSystemProviderSource { SOURCE_FILE, SOURCE_NETWORK, SOURCE_DEVICE };
+
+// Represents capabilities of a file system provider.
+class FileSystemProviderCapabilities : public Extension::ManifestData {
+ public:
+  FileSystemProviderCapabilities();

[not at google - send to devlin, 2015/04/24 16:18:32]

do you still need to define the default constructor?

[mtomasz, 2015/04/24 17:12:10]

Yes. I store capabilities as a member in ProvidingExtensionInfo (service.cc). I
also find it useful, as I can define default capabilities with the default
constructor.

+  FileSystemProviderCapabilities(bool configurable,
+                                 bool multiple_mounts,
+                                 FileSystemProviderSource source);
+  ~FileSystemProviderCapabilities() override;
+
+  // Returns capabilities of a providing |extension| if declared in the
+  // manifets. Otherwise NULL.
+  static const FileSystemProviderCapabilities* Get(const Extension* extension);
+
+  bool configurable() const { return configurable_; }
+  bool multiple_mounts() const { return multiple_mounts_; }
+  FileSystemProviderSource source() const { return source_; }
+
+ private:
+  bool configurable_;
+  bool multiple_mounts_;
+  FileSystemProviderSource source_;
+};
+
+// Parses the "file_system_provider" manifest key.
+class FileSystemProviderHandler : public ManifestHandler {
+ public:
+  FileSystemProviderHandler();
+  ~FileSystemProviderHandler() override;
+
+  // ManifestHandler overrides.
+  bool Parse(Extension* extension, base::string16* error) override;
+
+ private:
+  const std::vector<std::string> Keys() const override;
+
+  DISALLOW_COPY_AND_ASSIGN(FileSystemProviderHandler);
+};
+
+}  // namespace extensions
+
+#endif  // CHROME_COMMON_EXTENSIONS_API_FILE_SYSTEM_PROVIDER_FILE_SYSTEM_PROVIDER_HANDLER_H_