i#1551 port to ARM: stolen register on translation
i#1551 port to ARM: stolen register on translation

Restore stolen reg value when translating a machine context.

Review-URL: https://codereview.appspot.com/208600043

daksunt/dynamorio,code4bones/dynamorio,AmesianX/dynamorio,daksunt/dynamorio,bl4ckic3/dynamorio,daksunt/dynamorio,AmesianX/dynamorio,AmesianX/dynamorio,bl4ckic3/dynamorio,code4bones/dynamorio,code4bones/dynamorio,sigma-random/dynamorio,sigma-random/dynamorio,sigma-random/dynamorio,AmesianX/dynamorio,sigma-random/dynamorio,daksunt/dynamorio,daksunt/dynamorio,bl4ckic3/dynamorio,AmesianX/dynamorio,code4bones/dynamorio,bl4ckic3/dynamorio,sigma-random/dynamorio,bl4ckic3/dynamorio,code4bones/dynamorio