Fix dart-lang/markdown#142

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 1211b81..ed24f50 100644
--- a/pkgs/markdown/lib/src/block_parser.dart
+++ b/pkgs/markdown/lib/src/block_parser.dart
@@ -351,7 +351,7 @@
     var childLines = parseChildLines(parser);
 
     // Recursively parse the contents of the blockquote.
-    var children = parser.document.parseLines(childLines);
+    var children = new BlockParser(childLines, parser.document).parseLines();
 
     return new Element('blockquote', children);
   }