Baseline: 11f1a6d3ce529a63d4b7111c62ae504ceac2a019

Incompatible changes:

  - Remove --bep_publish_used_heap_size_post_build
  - JSON trace profile: rename counter names.

Important changes:

  - Adds --experimental_existing_rules_immutable_view flag to make the
    native.existing_rule and native.existing_rules functions more
    efficient by
    returning immutable, lightweight dict-like view objects instead
    of mutable
    dicts.

This release contains contributions from many people at Google, as well as Wren Turkal.