Fix avoid_redundant_argument_values lints (#2512)

diff --git a/lib/src/command/deps.dart b/lib/src/command/deps.dart
index d500779..4463b95 100644
--- a/lib/src/command/deps.dart
+++ b/lib/src/command/deps.dart
@@ -48,9 +48,7 @@
         defaultsTo: 'tree');
 
     argParser.addFlag('dev',
-        negatable: true,
-        help: 'Whether to include dev dependencies.',
-        defaultsTo: true);
+        help: 'Whether to include dev dependencies.', defaultsTo: true);
 
     argParser.addFlag('executables',
         negatable: false, help: 'List all available executables.');
diff --git a/lib/src/command/downgrade.dart b/lib/src/command/downgrade.dart
index 31a31f1..297f485 100644
--- a/lib/src/command/downgrade.dart
+++ b/lib/src/command/downgrade.dart
@@ -33,7 +33,7 @@
         negatable: false,
         help: "Report what dependencies would change but don't change any.");
 
-    argParser.addFlag('packages-dir', negatable: true, hide: true);
+    argParser.addFlag('packages-dir', hide: true);
   }
 
   @override
diff --git a/lib/src/command/get.dart b/lib/src/command/get.dart
index d9d72a6..24283e6 100644
--- a/lib/src/command/get.dart
+++ b/lib/src/command/get.dart
@@ -31,10 +31,9 @@
         help: "Report what dependencies would change but don't change any.");
 
     argParser.addFlag('precompile',
-        defaultsTo: false,
         help: 'Precompile executables in immediate dependencies.');
 
-    argParser.addFlag('packages-dir', negatable: true, hide: true);
+    argParser.addFlag('packages-dir', hide: true);
   }
 
   @override
diff --git a/lib/src/command/outdated.dart b/lib/src/command/outdated.dart
index 31b7a19..b1eb2d4 100644
--- a/lib/src/command/outdated.dart
+++ b/lib/src/command/outdated.dart
@@ -69,19 +69,17 @@
         defaultsTo: 'outdated');
 
     argParser.addFlag('prereleases',
-        defaultsTo: false, help: 'Include prereleases in latest version.');
+        help: 'Include prereleases in latest version.');
 
     // Preserve for backwards compatibility.
     argParser.addFlag('pre-releases',
-        defaultsTo: false, help: 'Alias of prereleases.', hide: true);
+        help: 'Alias of prereleases.', hide: true);
 
     argParser.addFlag('show-all',
-        defaultsTo: false,
         help: 'Include dependencies that are already fullfilling --mode.');
 
     // Preserve for backwards compatibility.
     argParser.addFlag('up-to-date',
-        defaultsTo: false,
         hide: true,
         help: 'Include dependencies that are already at the '
             'latest version. Alias of --show-all.');
diff --git a/lib/src/command/upgrade.dart b/lib/src/command/upgrade.dart
index b5a7c7d..299936c 100644
--- a/lib/src/command/upgrade.dart
+++ b/lib/src/command/upgrade.dart
@@ -33,10 +33,9 @@
         help: "Report what dependencies would change but don't change any.");
 
     argParser.addFlag('precompile',
-        defaultsTo: false,
         help: 'Precompile executables in immediate dependencies.');
 
-    argParser.addFlag('packages-dir', negatable: true, hide: true);
+    argParser.addFlag('packages-dir', hide: true);
   }
 
   @override
diff --git a/lib/src/solver/package_lister.dart b/lib/src/solver/package_lister.dart
index f1f9245..edf4bc7 100644
--- a/lib/src/solver/package_lister.dart
+++ b/lib/src/solver/package_lister.dart
@@ -264,7 +264,6 @@
           min: lower[package],
           includeMin: true,
           max: upper[package],
-          includeMax: false,
           alwaysIncludeMaxPreRelease: true);
 
       _alreadyListedDependencies[package] = constraint.union(
@@ -299,7 +298,6 @@
         max: bounds.last == versions.length - 1
             ? null
             : versions[bounds.last + 1].version,
-        includeMax: false,
         alwaysIncludeMaxPreRelease: true);
     _knownInvalidVersions = incompatibleVersions.union(_knownInvalidVersions);
 
diff --git a/lib/src/source/hosted.dart b/lib/src/source/hosted.dart
index 28bb36e..09c8f9b 100644
--- a/lib/src/source/hosted.dart
+++ b/lib/src/source/hosted.dart
@@ -169,8 +169,7 @@
   RateLimitedScheduler<PackageRef, Map<PackageId, _VersionInfo>> _scheduler;
 
   BoundHostedSource(this.source, this.systemCache) {
-    _scheduler =
-        RateLimitedScheduler(_fetchVersions, maxConcurrentOperations: 10);
+    _scheduler = RateLimitedScheduler(_fetchVersions);
   }
 
   Future<Map<PackageId, _VersionInfo>> _fetchVersions(PackageRef ref) async {
diff --git a/lib/src/validator/flutter_plugin_format.dart b/lib/src/validator/flutter_plugin_format.dart
index 43467be..6f00f06 100644
--- a/lib/src/validator/flutter_plugin_format.dart
+++ b/lib/src/validator/flutter_plugin_format.dart
@@ -53,7 +53,6 @@
               min: Version.parse('0.0.0'),
               max: Version.parse('1.10.0'),
               includeMin: true,
-              includeMax: false,
             )))) {
       errors.add('pubspec.yaml allows Flutter SDK version 1.9.x, which does '
           'not support the flutter.plugin.platforms key.\n'
diff --git a/test/oauth2/logout_test.dart b/test/oauth2/logout_test.dart
index d1dee58..23b2ecf 100644
--- a/test/oauth2/logout_test.dart
+++ b/test/oauth2/logout_test.dart
@@ -17,18 +17,14 @@
         .create();
 
     await runPub(
-        args: ['logout'],
-        output: contains('Logging out of pub.dartlang.org.'),
-        exitCode: 0);
+        args: ['logout'], output: contains('Logging out of pub.dartlang.org.'));
 
     await d.dir(cachePath, [d.nothing('credentials.json')]).validate();
   });
   test('with no existing credentials.json, notifies.', () async {
     await d.dir(cachePath, [d.nothing('credentials.json')]).create();
     await runPub(
-        args: ['logout'],
-        output: contains('No existing credentials file'),
-        exitCode: 0);
+        args: ['logout'], output: contains('No existing credentials file'));
 
     await d.dir(cachePath, [d.nothing('credentials.json')]).validate();
   });
diff --git a/test/utils_test.dart b/test/utils_test.dart
index c0d6067..c416951 100644
--- a/test/utils_test.dart
+++ b/test/utils_test.dart
@@ -94,8 +94,7 @@
     });
 
     test('does not display extra zero when duration is less than a minute', () {
-      expect(niceDuration(Duration(minutes: 0, seconds: 0, milliseconds: 400)),
-          equals('0.4s'));
+      expect(niceDuration(Duration(milliseconds: 400)), equals('0.4s'));
     });
 
     test('has reasonable output on minute boundary', () {