Merge "Intrinsify String.length() and String.isEmpty() as HIR."
am: 36a94ab70d

* commit '36a94ab70d4ae1ce239022a5841abf3ffe1196e3':
  Intrinsify String.length() and String.isEmpty() as HIR.

Change-Id: I194917b0e7930695908425a2a72270bcf453c525