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..77721c9207b105bf4f6b05e5d8f64a97da15b596 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"
@@ -72,16 +73,18 @@ class WEBKIT_STORAGE_EXPORT FileSystemContext
   // returns false if the current task is not running on the thread that allows
   // blocking file operations (like SequencedWorkerPool implementation does).
   //
-  // |external_mount_points| contains non-system external mount points available
-  // in the context. If not NULL, it will be used during URL cracking. On
-  // 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.
+  //
+  // |additional_mount_points| is used to crack FileSystemURL in
+  // CrackFileSystemURL() (in addition to default system-wide mount points).
   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 std::vector<MountPoints*>& additional_mount_points,
       const base::FilePath& partition_path,
       const FileSystemOptions& options);
 
@@ -193,9 +196,10 @@ class WEBKIT_STORAGE_EXPORT FileSystemContext
       int64 offset);
 
   // Register a filesystem provider. The ownership of |provider| is
-  // transferred to this instance.
-  void RegisterMountPointProvider(FileSystemType type,
-                                  FileSystemMountPointProvider* provider);
+  // transferred to this instance. This must be used only for testing.
+  void RegisterMountPointProviderForTesting(
+      FileSystemType type,
+      FileSystemMountPointProvider* provider);
 
   FileSystemTaskRunners* task_runners() { return task_runners_.get(); }
 
@@ -260,6 +264,10 @@ 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_;
@@ -267,15 +275,16 @@ class WEBKIT_STORAGE_EXPORT FileSystemContext
   // Regular mount point providers.
   scoped_ptr<SandboxMountPointProvider> sandbox_provider_;
   scoped_ptr<IsolatedMountPointProvider> isolated_provider_;
-  scoped_ptr<ExternalFileSystemMountPointProvider> external_provider_;
+
+  // Additional mount point providers.
+  ScopedVector<FileSystemMountPointProvider> additional_providers_;
 
   // Registered mount point providers.
+  // The map must be constructed in the constructor (other than for testing)
+  // since it can be accessed on multiple threads.
+  // The ownership of each provider is held by mount_point_providers_.
   std::map<FileSystemType, FileSystemMountPointProvider*> provider_map_;
 
-  // External mount points visible in the file system context (excluding system
-  // external mount points).
-  scoped_refptr<ExternalMountPoints> external_mount_points_;
-
   // MountPoints used to crack FileSystemURLs. The MountPoints are ordered
   // in order they should try to crack a FileSystemURL.
   std::vector<MountPoints*> url_crackers_;