Update partial parser and scanner to be able to skip expressions like "new Map<S, T>()".

dart/lib/compiler/implementation/scanner/array_based_scanner.dart

Index: dart/lib/compiler/implementation/scanner/array_based_scanner.dart
diff --git a/dart/lib/compiler/implementation/scanner/array_based_scanner.dart b/dart/lib/compiler/implementation/scanner/array_based_scanner.dart
index c3dfb5fc88c9dc003feef2910cb4624222f45dfa..c282f79421bd20689a70e3ff64c0137e13f306b1 100644
--- a/dart/lib/compiler/implementation/scanner/array_based_scanner.dart
+++ b/dart/lib/compiler/implementation/scanner/array_based_scanner.dart
@@ -49,6 +49,8 @@ class ArrayBasedScanner<S extends SourceString> extends AbstractScanner<S> {
   }
 
   void appendKeywordToken(Keyword keyword) {
+    final syntax = keyword.syntax;

[Lasse Reichstein Nielsen, 2012/06/15 11:51:13]

Please write the type of the variable. In this case it seems to be String, but
that isn't visible from anything except how it's used.
Omitting it does not increase readability, no matter what the style guide might
claim.

[ahe, 2012/06/15 13:12:34]

Good point.

Please be aware that when I'm writing code, you can pick one of these options
for a local variable: "final", "var", or a type. The combination of "final" and
type is not supported by me ;-)

+    if (syntax === 'this' || syntax === 'super') discardOpenLt();
     tail.next = new KeywordToken(keyword, tokenStart);
     tail = tail.next;
   }
@@ -90,11 +92,7 @@ class ArrayBasedScanner<S extends SourceString> extends AbstractScanner<S> {
     Token token = new BeginGroupToken(info, value, tokenStart);
     tail.next = token;
     tail = tail.next;
-    while (info.kind !== LT_TOKEN &&
-           !groupingStack.isEmpty() &&
-           groupingStack.head.kind === LT_TOKEN) {
-      groupingStack = groupingStack.tail;
-    }
+    if (info.kind !== LT_TOKEN) discardOpenLt();
     groupingStack = groupingStack.prepend(token);
   }