remove unused local variables

pkgs/markdown/lib/src/block_parser.dart

diff --git a/pkgs/markdown/lib/src/block_parser.dart b/pkgs/markdown/lib/src/block_parser.dart
index c34f7db..52ada6e 100644
--- a/pkgs/markdown/lib/src/block_parser.dart
+++ b/pkgs/markdown/lib/src/block_parser.dart
@@ -306,7 +306,6 @@
   const HorizontalRuleSyntax();
 
   Node parse(BlockParser parser) {
-    final match = pattern.firstMatch(parser.current);
     parser.advance();
     return new Element.empty('hr');
   }
@@ -374,7 +373,6 @@
       return match != null;
     }
 
-    bool afterEmpty = false;
     while (!parser.isDone) {
       if (tryMatch(_RE_EMPTY)) {
         // Add a blank line to the current list item.