A plan for method inlining in Jato

As a first step, we implement method inlining only for static method calls. This ensures that we know the method body to be inlined (as opposed to speculating for virtual calls).

High-level Algorithm
- Detect invokestatic instructions (STMT_INVOKE)
- For each argument
- replace pushing the argument with (STMT_STORE temp = arg_expr)
(Store the mapping between arguments and temporaries)
- Inline method body with references to local_0 to local_(nargs-1) replaced by references to the corresponding temporaries. Replace local variables with temporaries in a similar fashion.
- Convert return in method body to the following sequence of instructions
- ret_temp = return_expr; goto inlined_code_end (For STMT_RETURN)
- goto inlined_code_end (For STMT_VOID_RETURN)