Fix analyzer warnings in pkg/glob.

pkg/glob/lib/src/ast.dart

Index: pkg/glob/lib/src/ast.dart
diff --git a/pkg/glob/lib/src/ast.dart b/pkg/glob/lib/src/ast.dart
index 380aa5164b4e08c22b4001c6aecb580ffac203dc..dbb76e664c746009168c74fc78ebe50d75329aef 100644
--- a/pkg/glob/lib/src/ast.dart
+++ b/pkg/glob/lib/src/ast.dart
@@ -298,8 +298,8 @@ class RangeNode extends AstNode {
 
   bool operator==(Object other) {
     if (other is! RangeNode) return false;
-    if (other.negated != negated) return false;
-    return const SetEquality().equals(ranges, other.ranges);
+    if ((other as RangeNode).negated != negated) return false;
+    return const SetEquality().equals(ranges, (other as RangeNode).ranges);
   }
 
   int get hashCode => (negated ? 1 : 3) * const SetEquality().hash(ranges);