Elevate mapped types over type parameters in the same way as naked type parameters in intersection inference prioritization

[weswigham]

Fixes #33164

We should probably investigate if in the other places in inference where we check getInferenceInfoForType we should also be checking in a passthru-type way for homomrphic mapped types over a targeted type parameter, as I do here in the intersection case.

[weswigham]

@typescript-bot run dt
@typescript-bot test this
@typescript-bot user test this
@typescript-bot pack this for those vue people to validate that this fix applies in a non-minimized scenario

[typescript-bot]

Heya @weswigham, I've started to run the parallelized Definitely Typed test suite on this PR at 8bc3d76. You can monitor the build here. It should now contribute to this PR's status checks.

[typescript-bot]

Heya @weswigham, I've started to run the parallelized community code test suite on this PR at 8bc3d76. You can monitor the build here. It should now contribute to this PR's status checks.

[typescript-bot]

Heya @weswigham, I've started to run the tarball bundle task on this PR at 8bc3d76. You can monitor the build here. It should now contribute to this PR's status checks.

[typescript-bot]

Heya @weswigham, I've started to run the extended test suite on this PR at 8bc3d76. You can monitor the build here. It should now contribute to this PR's status checks.

[typescript-bot]

Hey @weswigham, I've packed this into an installable tgz. You can install it for testing by referencing it in your package.json like so:

{
    "devDependencies": {
        "typescript": "https://typescript.visualstudio.com/cf7ac146-d525-443c-b23c-0d58337efebc/_apis/build/builds/42647/artifacts?artifactName=tgz&fileId=6BD8376EF107FCDA03E661535DC92C380F628B1D6BE5DF60E07E81BA3E2F128E02&fileName=/typescript-3.7.0-insiders.20190903.tgz"
    }
}

and then running npm install.

[typescript-bot]

The user suite test run you requested has finished and failed. I've opened a PR with the baseline diff from master.

[weswigham]

user suite seems fine - it's just this morning's changes in the azure sdk (which I just accepted), plus today's continuing changes in vecode's build (they've patched their build to workaround issues with @types/node and ts 3.6), and office ui fabric (which is just some test updates).

[weswigham]

And RWC and DT are both clean, nice.

[weswigham]

@typescript-bot cherry-pick this into release-3.6

[typescript-bot]

Hey @weswigham, I've opened #33250 for you.