Revisit Analyzer class and related test infrastructure to better handle reattribution of live AST kind of issue

Objective is to better address reattributing live AST (for ex: https://bugs.openjdk.java.net/browse/JDK-8198502) kind of issues in a more general way.

1. Revisit if there was a reason for the analyzer code to be writtern as it was.
2. Improve test cases for this problem/to capture these kind of problem in a more general way.
3.Consider a more general way of addressing the issue not by duplicating the AST in analyzer.