Migrate pkg/build_integration to new constructor decl syntax.

(Part of #63288)

This change migrates `pkg/build_integration` to use the new
constructor declaration syntax, described in
https://github.com/dart-lang/language/blob/main/accepted/future-releases/primary-constructors/feature-specification.md#abbreviations-of-in-body-constructor-declarations.

This change was performed in an automated fashion, by (a) bumping the
packages' SDK constraints to `3.13.0-0`, (b) enabling the lints
`unnecessary_type_name_in_constructor` and
`unnecessary_const_in_enum_constructor`, (c) fixing the resulting lint
failures using `dart fix`, and then (d) reformatting the affected
files.

To ease code review, I've reverted unrelated formatting changes.

Since this change requires bumping SDK constaints to `3.13.0-0`, it
was only performed on packages that are *not* published on
pub. (Packages that *are* published on pub should remain on lower
language versions until at least after the stable version of 3.13 is
released, so that we don't block users on the stable channel from
receiving updates to those packages.)

Change-Id: Ifb2c4ca31f14c3e94f7b756969e730bf6a6a6964
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/506023
Reviewed-by: Nate Bosch <nbosch@google.com>
Commit-Queue: Paul Berry <paulberry@google.com>

Author: stereotype441

pkg/build_integration/analysis_options.yaml

@@ -1 +1,5 @@
+linter:
+  rules:
+    - unnecessary_type_name_in_constructor
+    - unnecessary_const_in_enum_constructor
 include: package:lints/recommended.yaml

pkg/build_integration/lib/file_system/multi_root.dart

@@ -36,7 +36,7 @@ class MultiRootFileSystem implements FileSystem {
   final List<Uri> roots;
   final FileSystem original;
 
-  MultiRootFileSystem(this.markerScheme, List<Uri> roots, this.original)
+  new(this.markerScheme, List<Uri> roots, this.original)
     : roots = roots.map(_normalize).toList();
 
   @override
@@ -74,7 +74,7 @@ class MultiRootFileSystemEntity implements FileSystemEntity {
     return multiRootFileSystem.original.entityForUri(uri);
   }
 
-  MultiRootFileSystemEntity(this.multiRootFileSystem, this.uri);
+  new(this.multiRootFileSystem, this.uri);
 
   @override
   Future<bool> exists() async => (await delegate).exists();
@@ -98,7 +98,7 @@ class MissingFileSystemEntity implements FileSystemEntity {
   @override
   final Uri uri;
 
-  MissingFileSystemEntity(this.uri);
+  new(this.uri);
 
   @override
   Future<bool> exists() => Future.value(false);

pkg/build_integration/lib/file_system/single_root.dart

@@ -31,8 +31,7 @@ class SingleRootFileSystem implements FileSystem {
   final Uri root;
   final FileSystem original;
 
-  SingleRootFileSystem(this.markerScheme, Uri root, this.original)
-    : root = _normalize(root);
+  new(this.markerScheme, Uri root, this.original) : root = _normalize(root);
 
   @override
   FileSystemEntity entityForUri(Uri uri) {
@@ -65,7 +64,7 @@ class SingleRootFileSystemEntity implements FileSystemEntity {
   final Uri uri;
   final FileSystemEntity delegate;
 
-  SingleRootFileSystemEntity(this.uri, this.delegate);
+  new(this.uri, this.delegate);
 
   @override
   Future<bool> exists() async => delegate.exists();

pkg/build_integration/pubspec.yaml

@@ -6,7 +6,7 @@ description: >
 publish_to: none
 
 environment:
-  sdk: '^3.12.0-0'
+  sdk: '^3.13.0-0'
 
 resolution: workspace