Properly parse friendly stack traces without columns.

pkg/stack_trace/lib/src/frame.dart

Index: pkg/stack_trace/lib/src/frame.dart
diff --git a/pkg/stack_trace/lib/src/frame.dart b/pkg/stack_trace/lib/src/frame.dart
index 797bef173ba1a6623bb1942ca3b4ad6a3c0076cf..45bef4d88e82c2316f4c391be5a89bd6039e59d4 100644
--- a/pkg/stack_trace/lib/src/frame.dart
+++ b/pkg/stack_trace/lib/src/frame.dart
@@ -23,7 +23,7 @@ final _v8Frame = new RegExp(
 // .VW.call$0("arg")@http://pub.dartlang.org/stuff.dart.js:560
 // .VW.call$0/name<@http://pub.dartlang.org/stuff.dart.js:560
 final _firefoxFrame = new RegExp(
-    r'^([^@(/]*)(?:\(.*\))?(/[^<]*<?)?(?:\(.*\))?@(.*):(\d+)$');
+    r'^([^@(/]*)(?:\(.*\))?((?:/[^/]*)*)(?:\(.*\))?@(.*):(\d+)$');
 
 // foo/bar.dart 10:11 in Foo._bar
 // http://dartlang.org/foo/bar.dart in Foo._bar
@@ -159,11 +159,9 @@ class Frame {
 
     var uri = Uri.parse(match[3]);
     var member = match[1];
-    if (member == "") {
-      member = "<fn>";
-    } else if (match[2] != null) {
-      member = "$member.<fn>";
-    }
+    member += new List.filled('/'.allMatches(match[2]).length, ".<fn>").join();
+    if (member == '') member = '<fn>';
+
     // Some Firefox members have initial dots. We remove them for consistency
     // with other platforms.
     member = member.replaceFirst(_initialDot, '');