message: Put superpack metadata in unpacker.py
  Summary: Support repacking in superpack
diff: @@ -109,7 +109,8 @@ class DexMetadata(object):
  have_locators=False,
  have_name_based_locators=False,
  is_root_relative=False,
  - locator_store_id=0):
  + locator_store_id=0,
  + superpack_files=0):
  self._have_locators = False
  self._have_name_based_locators = False
  self._store = store
  @@ -119,6 +120,7 @@ class DexMetadata(object):
  self._is_root_relative = is_root_relative
  self._dexen = []
  self._locator_store_id = locator_store_id
  + self.superpack_files = superpack_files
  def add_dex(self, dex_path, canary_class, hash=None):
  if hash is None:
  @@ -144,6 +146,8 @@ class DexMetadata(object):
  meta.write('.name_based_locators\n')
  if self._locator_store_id > 0:
  meta.write('.locator_id ' + str(self._locator_store_id) + '\n')
  + if self.superpack_files > 0:
  + meta.write('.superpack_files ' + str(self.superpack_files) + '\n')
  for dex in self._dexen:
  meta.write(' '.join(dex) + '\n')
  