assert: improve deep equal map

[BridgeAR]

This improves the performance for maps with object keys and for deepEqual loose equal primitive keys that contain primitives as value. The first part decreases the performance of the common case a tiny bit (primitive keys) in favor of the much slower worst case. Even though the common case must do a typecheck more I think it is favorable as it is also better to read that way.
In addition I updated a few comments.

 assert/deepequal-map.js method="deepEqual_looseMatches" len=1000 n=1000               16.85 %        *** 1.740720e-44
 assert/deepequal-map.js method="deepEqual_mixed" len=1000 n=1000                       2.14 %        *** 4.011895e-04
 assert/deepequal-map.js method="deepEqual_objectOnly" len=1000 n=1000                  3.45 %        *** 4.751408e-12
 assert/deepequal-map.js method="deepEqual_primitiveOnly" len=1000 n=1000              -2.52 %         ** 2.808637e-03
 assert/deepequal-map.js method="deepStrictEqual_mixed" len=1000 n=1000                 3.00 %        *** 7.353710e-07
 assert/deepequal-map.js method="deepStrictEqual_objectOnly" len=1000 n=1000            3.28 %        *** 6.647043e-09
 assert/deepequal-map.js method="deepStrictEqual_primitiveOnly" len=1000 n=1000        -1.01 %            4.022507e-01
 assert/deepequal-map.js method="notDeepEqual_looseMatches" len=1000 n=1000            16.35 %        *** 8.956366e-27
 assert/deepequal-map.js method="notDeepEqual_mixed" len=1000 n=1000                   -1.30 %            5.267886e-01
 assert/deepequal-map.js method="notDeepEqual_objectOnly" len=1000 n=1000               4.62 %        *** 2.039886e-14
 assert/deepequal-map.js method="notDeepEqual_primitiveOnly" len=1000 n=1000           -1.48 %          * 3.809026e-02
 assert/deepequal-map.js method="notDeepStrictEqual_mixed" len=1000 n=1000              0.92 %            6.739208e-01
 assert/deepequal-map.js method="notDeepStrictEqual_objectOnly" len=1000 n=1000         5.44 %        *** 4.738282e-19
 assert/deepequal-map.js method="notDeepStrictEqual_primitiveOnly" len=1000 n=1000     -1.59 %            1.132915e-01

Checklist

• make -j4 test (UNIX), or vcbuild test (Windows) passes
• tests and/or benchmarks are included
• documentation is changed or added
• commit message follows commit guidelines

Affected core subsystem(s)

assert

[jasnell]

ping @mscdex

[BridgeAR]

PTAL

[mscdex]

Without having reviewed the changes, I'd say the performance numbers are ok. I would just say be sure to re-run those benchmarks if/when backporting this PR to v6 and/or v4 to make sure that there are no more serious regressions due to Crankshaft, etc.

[refack]

Without having reviewed the changes, I'd say the performance numbers are ok.

Welcome back @mscdex 🤗

[refack]

Landed in 9222fe6
Extra sanity test of master: https://ci.nodejs.org/job/node-test-commit-linuxone/7939/ ✔️

[MylesBorins]

Not sure if we want to backport this to v6.x

[BridgeAR]

The same as #14258
Map and Set was added in v8. as a semver-major. I add the do not land labels.