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

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 class ArrayBasedScanner<S extends SourceString> extends AbstractScanner<S> {
   int get charOffset() => byteOffset + extraCharOffset;
   final Token tokens;
   Token tail;
   int tokenStart;
   int byteOffset;
@@ skipping 31 matching lines @@
     tail.next = new Token(info, tokenStart);
     tail = tail.next;
   }
 
   void appendStringToken(PrecedenceInfo info, String value) {
     tail.next = new StringToken(info, value, tokenStart);
     tail = tail.next;
   }
 
   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;
   }
 
   void appendEofToken() {
     tail.next = new Token(EOF_INFO, charOffset);
     tail = tail.next;
     // EOF points to itself so there's always infinite look-ahead.
     tail.next = tail;
     discardOpenLt();
@@ skipping 21 matching lines @@
   }
 
   void appendWhiteSpace(int next) {
     // Do nothing, we don't collect white space.
   }
 
   void appendBeginGroup(PrecedenceInfo info, String value) {
     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);
   }
 
   int appendEndGroup(PrecedenceInfo info, String value, int openKind) {
     assert(openKind !== LT_TOKEN);
     appendStringToken(info, value);
     discardOpenLt();
     if (groupingStack.isEmpty()) {
       return advance();
     }
@@ skipping 58 matching lines @@
 
   void discardOpenLt() {
     while (!groupingStack.isEmpty() && groupingStack.head.kind === LT_TOKEN) {
       groupingStack = groupingStack.tail;
     }
   }
 
   // TODO(ahe): make class abstract instead of adding an abstract method.
   abstract peek();
 }