This adds a baseline tier to the compilation pipeline. Currently this
tier is used to model a path from the interpreter to optimized code via
full-codegen code (to ensure sufficient type feedback). Switching from
the unoptimized tier to the baseline tier is limited to happen only when
there are no activations of the given function on the stack.

R=rmcilroy@chromium.org,bmeurer@chromium.org

Review URL: https://codereview.chromium.org/1903273004

Cr-Commit-Position: refs/heads/master@{#35757}