Don't adopt the AST id from previous if id is none, since previous may have mismatching expected stack height.
Additionally, harden merging of simulates after instructions with side effects and ensure there's a simulate before HEnterInlined.

R=jarin@chromium.org

Review URL: https://codereview.chromium.org/252583004

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@20967 ce2b1a6d-e550-0410-aec6-3dcde31c8c00