The JavaScript pipeline now consists of the following steps:

 1. Typed lowering.
 2. Representation selection (actually SimplifiedLowering).
 3. Early optimization pass (incl. JSGenericLowering).
 4. Effect control linearization (not for asm.js).
 5. Late optimization pass (incl. ChangeLowering).
 6. Real scheduling.

We should further cleanup the passes and restrict type and
representation information usage to appropriate parts of the pipeline.

R=jarin@chromium.org

Review URL: https://codereview.chromium.org/1907963002

Cr-Commit-Position: refs/heads/master@{#35702}