Fix filesystem API file_handlers to work for drive on ChromeOS.

webkit/fileapi/external_mount_points.h

Index: webkit/fileapi/external_mount_points.h
diff --git a/webkit/fileapi/external_mount_points.h b/webkit/fileapi/external_mount_points.h
index a2660c24536d118b643e29f8baadc9fadeb786fb..1d912aa2e29f280ac984f6ae2a1c2b7fee83cc76 100644
--- a/webkit/fileapi/external_mount_points.h
+++ b/webkit/fileapi/external_mount_points.h
@@ -86,11 +86,12 @@ class WEBKIT_STORAGE_EXPORT ExternalMountPoints
       FileSystemType type,
       const base::FilePath& path) const OVERRIDE;
 
-  // Retrieves the remote file system proxy for the registered file system.
-  // Returns NULL if there is no file system with the given name, or if the file
-  // system does not have a remote file system proxy.
-  RemoteFileSystemProxyInterface* GetRemoteFileSystemProxy(
-      const std::string& mount_name) const;
+  // Retrieves the remote file system proxy for a path on a registered file
+  // system.
+  // Returns NULL if there is no file system for the path, or if the file system
+  // does not have a remote file system proxy.
+  RemoteFileSystemProxyInterface* GetRemoteFileSystemProxyForPath(
+      const base::FilePath& full_path) const;
 
   // Returns a list of registered MountPointInfos (of <mount_name, path>).
   void AddMountPointInfosTo(std::vector<MountPointInfo>* mount_points) const;
@@ -136,6 +137,16 @@ class WEBKIT_STORAGE_EXPORT ExternalMountPoints
   bool ValidateNewMountPoint(const std::string& mount_name,
                              const base::FilePath& path);
 
+  // Sets |mount_point_name| and |mount_point_root| to the name and root path of
+  // the mount point that |path| belongs to. |mount_point_root| may be NULL in
+  // which case it is ignored.
+  // If the path doesn't belong to any of the mount points, both
+  // |mount_point_name| and |mount_point_root| are not changed.
+  // Returns whether the mount point could be found.
+  bool GetMountPointForPath(const base::FilePath& path,
+                            std::string* mount_point_name,
+                            base::FilePath* mount_point_root) const;
+
   // This lock needs to be obtained when accessing the instance_map_.
   mutable base::Lock lock_;