Fix strong mode warnings and errors.

lib/src/parser.dart

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 import 'package:path/path.dart' as p;
 import 'package:string_scanner/string_scanner.dart';
 
 import 'ast.dart';
 import 'utils.dart';
 
@@ skipping 15 matching lines @@
       : _scanner = new StringScanner(component),
         _caseSensitive = caseSensitive;
 
   /// Parses an entire glob.
   SequenceNode parse() => _parseSequence();
 
   /// Parses a [SequenceNode].
   ///
   /// If [inOptions] is true, this is parsing within an [OptionsNode].
   SequenceNode _parseSequence({bool inOptions: false}) {
-    var nodes = [];
+    var nodes = <AstNode>[];
 
     if (_scanner.isDone) {
       _scanner.error('expected a glob.', position: 0, length: 0);
     }
 
     while (!_scanner.isDone) {
       if (inOptions && (_scanner.matches(',') || _scanner.matches('}'))) break;
       nodes.add(_parseNode(inOptions: inOptions));
     }
 
@@ skipping 45 matching lines @@
     if (_scanner.matches(']')) _scanner.error('unexpected "]".');
     var negated = _scanner.scan('!') || _scanner.scan('^');
 
     readRangeChar() {
       var char = _scanner.readChar();
       if (negated || char != _SLASH) return char;
       _scanner.error('"/" may not be used in a range.',
           position: _scanner.position - 1);
     }
 
-    var ranges = [];
+    var ranges = <Range>[];
     while (!_scanner.scan(']')) {
       var start = _scanner.position;
       // Allow a backslash to escape a character.
       _scanner.scan('\\');
       var char = readRangeChar();
 
       if (_scanner.scan('-')) {
         if (_scanner.matches(']')) {
           ranges.add(new Range.singleton(char));
           ranges.add(new Range.singleton(_HYPHEN));
@@ skipping 20 matching lines @@
         negated: negated, caseSensitive: _caseSensitive);
   }
 
   /// Tries to parse an [OptionsNode].
   ///
   /// Returns `null` if there's not one to parse.
   AstNode _parseOptions() {
     if (!_scanner.scan('{')) return null;
     if (_scanner.matches('}')) _scanner.error('unexpected "}".');
 
-    var options = [];
+    var options = <SequenceNode>[];
     do {
       options.add(_parseSequence(inOptions: true));
     } while (_scanner.scan(','));
 
     // Don't allow single-option blocks.
     if (options.length == 1) _scanner.expect(',');
     _scanner.expect('}');
 
     return new OptionsNode(options, caseSensitive: _caseSensitive);
   }
@@ skipping 16 matching lines @@
 
     for (var char in const [']', '(', ')']) {
       if (_scanner.matches(char)) _scanner.error('unexpected "$char"');
     }
     if (!inOptions && _scanner.matches('}')) _scanner.error('unexpected "}"');
 
     return new LiteralNode(buffer.toString(),
         context: _context, caseSensitive: _caseSensitive);
   }
 }