Rename `PathResolution` to `PartialRes`

Don't use `PartialRes` when `Res` is enough.
Rename `Res::kind_name` to `Res::descr` for consistency.
Remove `Res::Label`, paths can never resolve to labels.

Some further cleanup after https://github.com/rust-lang/rust/pull/60462
r? @EddyB

rustc: collapse relevant DefPathData variants into {Type,Value,Macro,Lifetime}Ns.

`DefPathData` was meant to disambiguate within each namespace, but over the years, that purpose was overlooked, and it started to serve a double-role as a sort of `DefKind` (which #60462 properly adds).
Now, we can go back to *only* categorizing namespaces (at least for the variants with names in them).

r? @petrochenkov or @nikomatsakis cc @michaelwoerister

Fix substs issues for const errors

Fixes https://github.com/rust-lang/rust/issues/60503.

build dist-aarch64-linux with --enable-profiler

This change should enable PGO to be used for aarch64-linux.

Fixes #57257.

Fix #45268 by saving all NodeId's for resolved traits.

This fixes #45268 by saving all NodeId's for resolved traits.

I've verifies this against master (but only on MacOS). However, with some recent changes in master, it appears that there are some failures on my machine. They are unrelated to my changes, anyway.

Paths can never resolve to labels

Don't use `PartialRes` when `Res` is enough

submodules: update clippy from 2ed0b3bf to fc96aa03

Changes:
````
Rustup to rustc 1.36.0-nightly (13fde05b 2019-05-03)
Fix link in into_iter_on_array documentation
remove function body from "too many args" span
check closure arguments before use it
format code
fix suggestion for search_is_some
fix suggestion for search_is_some naively
change |&x| to |x| in stderr file
cargo fmt
useless_let_if_seq handle interior mutability
````
Fixes https://github.com/rust-lang/rust/issues/60534

Categorize WASI as an "OS" rather than as an "environment".

This distinction is fairly abstract, but in practice, the main advantage
here is that LLVM's triple code considers WASI to be an OS, so this
makes rustc agree with that.

Changes:
````
Rustup to rustc 1.36.0-nightly (13fde05b 2019-05-03)
Fix link in into_iter_on_array documentation
remove function body from "too many args" span
check closure arguments before use it
format code
fix suggestion for search_is_some
fix suggestion for search_is_some naively
change |&x| to |x| in stderr file
cargo fmt
useless_let_if_seq handle interior mutability
````

Rollup of 9 pull requests

Successful merges:

 - #60429 (Account for paths in incorrect pub qualifier help)
 - #60449 (Constrain all regions in the concrete type for an opaque type)
 - #60486 (Place related refactors)
 - #60513 (Remove -Z borrowck=compare flag)
 - #60516 (Remove TypeckMir)
 - #60517 (Reword casting message)
 - #60520 (Add rustfmt toml)
 - #60521 (Migrate tidy to rust 2018 edition)
 - #60527 (Fix async fn lowering ICE with APIT.)

Failed merges:

r? @ghost

Fix async fn lowering ICE with APIT.

Fixes #60518.

This PR fixes an ICE where simple bindings (which aren't replaced with replacement arguments during async fn lowering) were not being visited in the def collector and thus caused an ICE during HIR lowering for types that use their `DefId` at that point - such as `impl Trait`.

r? @cramertj

Migrate tidy to rust 2018 edition

cc @Centril

Add rustfmt toml

This commit adds an rustfmt.toml for using for **new** code.
Old code should continut to use old style, until we put automated
style checks in place.

See
https://internals.rust-lang.org/t/running-rustfmt-on-rust-lang-rust-and-other-rust-lang-repositories/8732/81
for the reason why we deviate from the default formatting. The TL;DR
is that currently compiler uses a pretty condensed style of code, and
default settings both create a huge diff and inflate the number of
lines. use_small_heuristics=Max fixes that.

version=Two is required for bug-fixes, which technically can't be made
to the stable first version

cc @Centril: I guess adding config file with agreed-upon formatting doesn't hurt :-)

EDIT: Zullip discussion: https://rust-lang.zulipchat.com/#narrow/stream/131828-t-compiler/topic/x.2Epy.20fmt

Reword casting message

r? @davidtwco

Remove TypeckMir

Fixes #60422

r? @matthewjasper

Remove -Z borrowck=compare flag

This is the start of the work that needs to be done on #59193. It just removes the flag and updates
the tests.

r? @matthewjasper

Place related refactors

Meanwhile I was working on Place 2 I'm finding some little things that I had on my branch but preferred to land a separate PR for things that are simpler to merge.

r? @oli-obk

Constrain all regions in the concrete type for an opaque type

`push_outlives_components` skips some regions in a type, notably the signature
of a closure is ignored. Most of the time this is OK, but for opaque types the
concrete type is used when checking auto-trait bounds in other functions.

cc @nikomatsakis @pnkfelix

Closes #57464
Closes #60127

Account for paths in incorrect pub qualifier help

Handle case where incorrect pub qualifier with a mod path is used and provide the same help given for all other incorrect qualifiers by making the `pub(crate)` parse check more specific.

This distinction is fairly abstract, but in practice, the main advantage
here is that LLVM's triple code considers WASI to be an OS, so this
makes rustc agree with that.

Multi-variant layouts for generators

This allows generators to overlap fields using variants, but doesn't do any such overlapping yet. It creates one variant for every state of the generator (unresumed, returned, panicked, plus one for every yield), and puts every stored local in each of the yield-point variants.

Required for optimizing generator layouts (#52924).

There was quite a lot of refactoring needed for this change. I've done my best in later commits to eliminate assumptions in the code that only certain kinds of types are multi-variant, and to centralize knowledge of the inner mechanics of generators in as few places as possible.

This change also emits debuginfo about the fields contained in each variant, as well as preserving debuginfo about stored locals while running in the generator.

Also, fixes #59972.

Future work:
- Use this change for an optimization pass that actually overlaps locals within the generator struct (#52924)
- In the type layout fields, don't include locals that are uninitialized for a particular variant, so miri and UB sanitizers can check our memory (see https://github.com/rust-lang/rust/issues/59972#issuecomment-483058172)
- Preserve debuginfo scopes across generator yield points