Use Idents for fields in HIR

[petrochenkov]

Continuation of #49718, part of #49300

[rust-highfive]

r? @cramertj

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[petrochenkov]

r? @eddyb

[rust-highfive]

The job x86_64-gnu-llvm-3.9 of your PR failed on Travis (raw log). Through arcane magic we have determined that the following fragments from the build log may contain information about the problem.

Click to expand the log.

Requirement already satisfied: PyYAML<=3.12,>=3.10 in /usr/lib/python2.7/dist-packages (from awscli)
Collecting botocore==1.10.28 (from awscli)
/usr/local/lib/python2.7/dist-packages/pip/_vendor/requests/packages/urllib3/util/ssl_.py:122: InsecurePlatformWarning: A true SSLContext object is not available. This prevents urllib3 from configuring SSL appropriately and may cause certain SSL connections to fail. You can upgrade to a newer version of Python to solve this. For more information, see https://urllib3.readthedocs.io/en/latest/security.html#insecureplatformwarning.
  InsecurePlatformWarning
  Downloading https://files.pythonhosted.org/packages/2e/91/f0870d4de8eb78897ce781f3ff22fc492bbb9849b5c91f26db20b125ef36/botocore-1.10.28-py2.py3-none-any.whl (4.2MB)
    0% |                                | 10kB 43.6MB/s eta 0:00:01
    0% |▏                               | 20kB 40.1MB/s eta 0:00:01
    0% |▎                               | 30kB 47.4MB/s eta 0:00:01
    0% |▎                               | 40kB 18.2MB/s eta 0:00:01
---
[00:33:38]    Compiling aho-corasick v0.6.4
[00:33:44]    Compiling tempdir v0.3.7
[00:34:15]    Compiling minifier v0.0.11
[00:34:17]    Compiling rustdoc v0.0.0 (file:///checkout/src/librustdoc)
[00:34:22] error[E0609]: no field `name` on type `&&rustc::ty::FieldDef`
[00:34:22]     --> librustdoc/clean/mod.rs:1094:75
[00:34:22]      |
[00:34:22] 1094 |                         cx.tcx.adt_def(did).all_fields().find(|item| item.name == item_name)
[00:34:22] 
[00:34:22] 
[00:34:22] error[E0609]: no field `name` on type `&&rustc::ty::FieldDef`
[00:34:22]     --> librustdoc/clean/mod.rs:1100:49
[00:34:22]      |
[00:34:22] 1100 |                               .find(|item| item.name == item_name)
[00:34:22] 
[00:34:22] error[E0609]: no field `name` on type `&rustc::ty::FieldDef`
[00:34:22]     --> librustdoc/clean/mod.rs:1106:47
[00:34:22]      |
[00:34:22]      |
[00:34:22] 1106 |                                          item.name))))
[00:34:22] 
[00:34:24] error[E0609]: no field `name` on type `&rustc::hir::StructField`
[00:34:24]     --> librustdoc/clean/mod.rs:2993:29
[00:34:24]      |
[00:34:24]      |
[00:34:24] 2993 |             name: Some(self.name).clean(cx),
[00:34:24] 
[00:34:24] error[E0609]: no field `name` on type `&rustc::ty::FieldDef`
[00:34:24]     --> librustdoc/clean/mod.rs:3008:29
[00:34:24]      |
[00:34:24]      |
[00:34:24] 3008 |             name: Some(self.name).clean(cx),
[00:34:24] 
[00:34:24] error[E0609]: no field `name` on type `&rustc::ty::FieldDef`
[00:34:24]     --> librustdoc/clean/mod.rs:3204:46
[00:34:24]      |
[00:34:24]      |
[00:34:24] 3204 |                             name: Some(field.name.clean(cx)),
[00:34:24] 
[00:34:24] 
[00:34:24] error[E0609]: no field `name` on type `&rustc::hir::FieldPat`
[00:34:24]     --> librustdoc/clean/mod.rs:3853:56
[00:34:24]      |
[00:34:24] 3853 |                                   format!("{}: {}", fp.name, name_from_pat(&*fp.pat)))
[00:34:24] 
own-linux-gnu/stage0-sysroot/lib
70344 ./obj/build/x86_64-unknown-linux-gnu/stage0-sysroot/lib/rustlib
70340 ./obj/build/x86_64-unknown-linux-gnu/stage0-sysroot/lib/rustlib/x86_64-unknown-linux-gnu

I'm a bot! I can only do what humans tell me to, so if this was not helpful or you have suggestions for improvements, please ping or otherwise contact @TimNN. (Feature Requests)

[eddyb]

r=me with rustdoc fixed

[petrochenkov]

@bors r=eddyb

[bors]

📌 Commit 1e4269c has been approved by eddyb

[petrochenkov]

@bors p=1
Conflict prone

[bors]

⌛ Testing commit 1e4269c with merge 1e504d3...

[bors]

☀️ Test successful - status-appveyor, status-travis
Approved by: eddyb
Pushing 1e504d3 to master...