The functionality of the GetIterator bytecode introduced previously is
now extended from loading the @@iterator property to calling the property
as well. This change basically absorbs the functionality of additional
two bytecodes - Star, CallProperty0 in the GetIterator bytecode.
Importantly, this change handles the cases of eager and lazy deoptimization
in the middle of the bytecode, i.e., lazy deopt for LdaNamedProperty and
eager deopt of the CallProperty0 bytecode, using the continuation builtins.
This mechanism can work as a template for the future bytecode that require
handling such inter-bytecode deopt scenario. The tests evaluating the eager
and lazy deopt scenarios are also included.

Bug: v8:9489
Change-Id: I93eb022bbc3d37582407820aa8482a343cac6c12
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1758313
Commit-Queue: Swapnil Gaikwad <swapnilgaikwad@google.com>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63528}