Handle multiline interpolated strings in line-based scanner.

dart/tests/try/paste_content_rewriting_test.dart

Index: dart/tests/try/paste_content_rewriting_test.dart
diff --git a/dart/tests/try/paste_content_rewriting_test.dart b/dart/tests/try/paste_content_rewriting_test.dart
index 6583c75f06720c4db5aebce3553b7eec63dab6a8..0d192a6021094df014721b3d8b166105d7ff959a 100644
--- a/dart/tests/try/paste_content_rewriting_test.dart
+++ b/dart/tests/try/paste_content_rewriting_test.dart
@@ -31,6 +31,8 @@ const Map<String, String> tests = const <String, String> {
   'r"""\n\n\'"""': 'r"""\n\n\'"""',
   '"': '<DIAGNOSTIC>"</DIAGNOSTIC>',
   '/**\n*/': '/**\n*/',
+  '"\${ [ "\${ [ \'\${ { \'\${\n{\n} }\' : {\n} } }\' ] }" ] }"':

[kasperl, 2014/07/07 11:16:39]

Add a comment that explains what this is?

[ahe, 2014/07/09 10:11:13]

Done.

+  '"\${ [ "\${ [ \'\${ { \'\${\n{\n} }\' : {\n} } }\' ] }" ] }"',

[ahe, 2014/07/07 09:36:55]

The best test I have found so far simply ensures that no diagnostics are added
to the above.

 };
 
 List<Node> queryDiagnosticNodes() {