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

dart/lib/compiler/implementation/scanner/partial_parser.dart

Index: dart/lib/compiler/implementation/scanner/partial_parser.dart
diff --git a/dart/lib/compiler/implementation/scanner/partial_parser.dart b/dart/lib/compiler/implementation/scanner/partial_parser.dart
index 1e792d0410d289bdf483dfab28e04626e6489b8f..b805c92f65fbbe8d1bf9075bbc645100de49adcd 100644
--- a/dart/lib/compiler/implementation/scanner/partial_parser.dart
+++ b/dart/lib/compiler/implementation/scanner/partial_parser.dart
@@ -56,7 +56,7 @@ class PartialParser extends Parser {
       }
       if (!mayParseFunctionExpressions && value === '{')

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

While you are here, please put curly braces around this return.

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

No need. It fits on the previous line.

[Lasse Reichstein Nielsen, 2012/06/15 13:59:14]

I generally prefer to put return statements on a line by themselves, instead of
hiding them at the end of a line (except for when I don't, ofcourse).
It's because I see "return" (and "throw") as control flow operations, and I
prefer to have only one control-flow operation per line.

[ahe, 2012/06/19 11:02:42]

OK. We have used the "bailout" return can go on the same line in other places.

         return token;
-      if ((value !== '<') && (token is BeginGroupToken)) {
+      if (token is BeginGroupToken) {
         BeginGroupToken begin = token;
         token = (begin.endGroup !== null) ? begin.endGroup : token;
       }