Enable cross-filesystem moves and copies.

webkit/fileapi/file_system_file_util.h

Index: webkit/fileapi/file_system_file_util.h
diff --git a/webkit/fileapi/file_system_file_util.h b/webkit/fileapi/file_system_file_util.h
index 5df8cd4f164ed01ef7e49f2014612eb005591532..d6b72e6ff99fe9fbdc88b84362ec88d7677d239f 100644
--- a/webkit/fileapi/file_system_file_util.h
+++ b/webkit/fileapi/file_system_file_util.h
@@ -116,6 +116,14 @@ class FileSystemFileUtil {
       const FilePath& dest_file_path,
       bool copy);
 
+  // Copies in a single file from a different filesystem.  The src_file_path is
+  // a true local platform path, regardless of which subclass of
+  // FileSystemFileUtil is being invoked.
+  virtual PlatformFileError CopyInForeignFile(
+        FileSystemOperationContext* context,
+        const FilePath& src_file_path,
+        const FilePath& dest_file_path);
+
   // Copies a file or a directory from |src_file_path| to |dest_file_path|.
   //
   // Error cases:
@@ -254,6 +262,16 @@ class FileSystemFileUtil {
       const FilePath& dest_file_path,
       bool copy);
 
+  // Determines whether a simple same-filesystem move or copy can be done.  If
+  // so, it delegates to CopyOrMoveFile.  Otherwise it looks up the true
+  // platform path of the source file, delegates to CopyInForeignFile, and [for
+  // move] calls DeleteFile on the source file.
+  PlatformFileError CopyOrMoveFileHelper(
+      FileSystemOperationContext* context,
+      const FilePath& src_file_path,
+      const FilePath& dest_file_path,
+      bool copy);
+
   // Returns a pointer to a new instance of AbstractFileEnumerator which is
   // implemented for each FileUtil subclass. The instance needs to be freed
   // by the caller, and its lifetime should not extend past when the current