Revert of [cleanup] CodeStubAssembler: s/compiler::Node/Node/ (patchset #2 id:20001 of https://codereview.chromium.org/2519093002/ )

Reason for revert:
Blocks revert of roll blocker: https://codereview.chromium.org/2528583002/

Original issue's description:
> [cleanup] CodeStubAssembler: s/compiler::Node/Node/
>
> Reducing visual clutter.
>
> Committed: https://crrev.com/36a17e87d86d2d978b64eb37044c9e9f98ebea67
> Cr-Commit-Position: refs/heads/master@{#41187}

TBR=ishell@chromium.org,jkummerow@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Review-Url: https://codereview.chromium.org/2528593002
Cr-Commit-Position: refs/heads/master@{#41206}