Ensure we keep receiver type information when TFA de-virtualizes calls

[mkustermann]

When TFA de-virtualizes instance calls into static calls we might loose the inferred type information on the receiver.

Currently we have ad-hoc code for strengthening the type of the receiver based on the target of a static call instruction, e.g. in the AOT call specializer . We should ensure the type information is already attached from the very beginning, instead of "re-computing" based on the target of a static call. Also the TFA might have a more precise receiver type than the we can re-compute based on the target (since that can be in a super class).

@mraleph @alexmarkov