Removes most[1] explicit calls to GetIsolate() in parsing/ by passing
it through calling function functions and implicit calls via the single
argument Handle constructor and handle function.

[1] One remains in preparsed-scope-data.cc:
data_->GetIsolate()->PushStackTraceAndDie()

Bug: v8:7786
Change-Id: I4c445995a73c19bdf4649b65487b7443d56ddd2a
Reviewed-on: https://chromium-review.googlesource.com/1085057Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Commit-Queue: Dan Elphick <delphick@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53513}