Make MountPointProvider pluggable from outside webkit/fileapi

webkit/fileapi/file_system_context.h

Index: webkit/fileapi/file_system_context.h
diff --git a/webkit/fileapi/file_system_context.h b/webkit/fileapi/file_system_context.h
index 0225a219ba320a311b780d4df1481d3e4ae64b4a..95e736a9c95e861df1e383e45fb8805ab651dc5a 100644
--- a/webkit/fileapi/file_system_context.h
+++ b/webkit/fileapi/file_system_context.h
@@ -12,6 +12,7 @@
 #include "base/callback.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
+#include "base/memory/scoped_vector.h"
 #include "base/platform_file.h"
 #include "base/sequenced_task_runner_helpers.h"
 #include "webkit/fileapi/file_system_types.h"
@@ -77,11 +78,17 @@ class WEBKIT_STORAGE_EXPORT FileSystemContext
   // ChromeOS, it will be passed to external_mount_point_provider.
   // |external_mount_points| may be NULL only on platforms different from
   // ChromeOS (i.e. platforms that don't use external_mount_point_provider).
+  //
+  // |additional_providers| are added to the internal provider map
+  // to serve filesystem requests for non-regular types.
+  // If none is given, this context only handles HTML5 Sandbox FileSystem
+  // and Drag-and-drop Isolated FileSystem requests.
   FileSystemContext(
       scoped_ptr<FileSystemTaskRunners> task_runners,
       ExternalMountPoints* external_mount_points,
       quota::SpecialStoragePolicy* special_storage_policy,
       quota::QuotaManagerProxy* quota_manager_proxy,
+      ScopedVector<FileSystemMountPointProvider> additional_providers,
       const base::FilePath& partition_path,
       const FileSystemOptions& options);
 
@@ -192,11 +199,6 @@ class WEBKIT_STORAGE_EXPORT FileSystemContext
       const FileSystemURL& url,
       int64 offset);
 
-  // Register a filesystem provider. The ownership of |provider| is
-  // transferred to this instance.
-  void RegisterMountPointProvider(FileSystemType type,
-                                  FileSystemMountPointProvider* provider);
-
   FileSystemTaskRunners* task_runners() { return task_runners_.get(); }
 
   sync_file_system::LocalFileChangeTracker* change_tracker() {
@@ -221,6 +223,9 @@ class WEBKIT_STORAGE_EXPORT FileSystemContext
                                            const base::FilePath& path) const;
 
  private:
+  typedef std::map<FileSystemType, FileSystemMountPointProvider*>
+      MountPointProviderMap;
+
   // Friended for GetFileUtil.
   // These classes know the target filesystem (i.e. sandbox filesystem)
   // supports synchronous FileUtil.
@@ -260,6 +265,10 @@ class WEBKIT_STORAGE_EXPORT FileSystemContext
   // does not support synchronous file operations.
   FileSystemFileUtil* GetFileUtil(FileSystemType type) const;
 
+  // For initial provider_map construction. This must be called only from
+  // the constructor.
+  void RegisterMountPointProvider(FileSystemMountPointProvider* provider);
+
   scoped_ptr<FileSystemTaskRunners> task_runners_;
 
   scoped_refptr<quota::QuotaManagerProxy> quota_manager_proxy_;
@@ -269,9 +278,14 @@ class WEBKIT_STORAGE_EXPORT FileSystemContext
   scoped_ptr<IsolatedMountPointProvider> isolated_provider_;
   scoped_ptr<ExternalFileSystemMountPointProvider> external_provider_;
 
-  // Registered mount point providers.
-  std::map<FileSystemType, FileSystemMountPointProvider*> provider_map_;
+  // Additional mount point providers.
+  ScopedVector<FileSystemMountPointProvider> additional_providers_;
 
+  // Registered mount point providers.
+  // The map must be constructed in the constructor since it can be accessed
+  // on multiple threads.
+  // The ownership of each provider is held by mount_point_providers_.
+  MountPointProviderMap provider_map_;
   // External mount points visible in the file system context (excluding system
   // external mount points).
   scoped_refptr<ExternalMountPoints> external_mount_points_;