Reland "linter 1.4.0"

This is a reland of 17644ee

Additional supporting changes in flutter (and plugins):

flutter/flutter#81017
flutter/plugins#3823
flutter/flutter#80817
flutter/flutter#80901
flutter/flutter#81210

Additional context in meta linter issue: dart-lang/linter#2609





Original change's description:
> linter 1.4.0
>
> Mitigating PRs:
>
> https://dart-review.googlesource.com/c/sdk/+/196223
> https://dart-review.googlesource.com/c/sdk/+/196180
>
> flutter/flutter#80817
> flutter/flutter#80901
>
>
>
>
>
> Change-Id: Ib916d541076e24b9e8db1d6120dbc043d9e40b87
> Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/196026
> Commit-Queue: Phil Quitslund <[email protected]>
> Reviewed-by: Brian Wilkerson <[email protected]>

Change-Id: Ie6b9682a2f54ef039dd7ac9c6a46cb925615acef
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/196581
Commit-Queue: Phil Quitslund <[email protected]>
Reviewed-by: Brian Wilkerson <[email protected]>

CHANGELOG.md

@@ -38,14 +38,14 @@
 
 #### Linter
 
-Updated the Linter to `1.3.0`, which includes:
+Updated the Linter to `1.4.0`, which includes:
 
-- updated `non_constant_identifier_names` to check local variables, for-loop
-  initializers and catch clauses.
-- updated error range of `lines_longer_than_80_chars` to start at 80 to make
-  splitting easier.
-- new lint: `require_trailing_commas`.
-- new lint: `prefer_null_aware_method_calls`.
+- `directives_ordering` now checks ordering of `package:` imports in code
+  outside pub packages.
+- simple reachability analysis added to `use_build_context_synchronously` to
+  short-circuit await-discovery in terminating blocks.
+- `use_build_context_synchronously` updated to recognize nullable types when
+  accessed from legacy libraries.
 
 ### Language
 
@@ -5738,4 +5738,4 @@ documentation on the [Dart API site](http://api.dartlang.org).
     compression.
 
 * `dart:isolate`: `Isolate.spawnUri` added the optional `packageRoot` argument,
-  which controls how it resolves `package:` URIs.
+  which controls how it resolves `package:` URIs.

DEPS

@@ -124,7 +124,7 @@ vars = {
   "intl_tag": "0.17.0-nullsafety",
   "jinja2_rev": "2222b31554f03e62600cd7e383376a7c187967a1",
   "json_rpc_2_rev": "5ec32a2e0e99dedcef5b3237f93167cd22c2da50",
-  "linter_tag": "1.3.0",
+  "linter_tag": "1.4.0",
   "logging_rev": "e2f633b543ef89c54688554b15ca3d7e425b86a2",
   "markupsafe_rev": "8f45f5cfa0009d2a70589bcda0349b8cb2b72783",
   "markdown_rev": "9c4beaac96d8f008078e00b027915f81b665d2de",
@@ -725,4 +725,4 @@ hooks = [
     ],
     'condition': 'checkout_win'
   },
-]
+]