We're moving away from using CompilationInfo as a big bag o' stuff.
Passing in just what we need to several AstVisitors to avoid
increasing the problem.

BUG=None
TEST=trybots
R=titzer@chromium.org
LOG=N

Review URL: https://codereview.chromium.org/1318823010

Cr-Commit-Position: refs/heads/master@{#30529}