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

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

Index: dart/lib/compiler/implementation/scanner/scanner.dart
diff --git a/dart/lib/compiler/implementation/scanner/scanner.dart b/dart/lib/compiler/implementation/scanner/scanner.dart
index 2dd4d38891b8ceed534189afce0409ad42be88c2..c6c5f2fd28af96c0540e3d974f7e5432a49d47a5 100644
--- a/dart/lib/compiler/implementation/scanner/scanner.dart
+++ b/dart/lib/compiler/implementation/scanner/scanner.dart
@@ -33,6 +33,13 @@ class AbstractScanner<T extends SourceString> implements Scanner {
   abstract void appendGt(PrecedenceInfo info, String value);
   abstract void appendGtGt(PrecedenceInfo info, String value);
   abstract void appendGtGtGt(PrecedenceInfo info, String value);
+
+  /**
+   * We call this method to discard '<' from the "grouping" stack
+   * (maintained by subclasses). That we don't create groups for stuff
+   * like "a = b < c, d = e > f" is used by
+   * [PartialParser.skipExpression].
+   */

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

So you call this when you recognize something that can't possibly be part of a
type parameter/type argument?

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

Done.

   abstract void discardOpenLt();
 
   // TODO(ahe): Move this class to implementation.
@@ -143,6 +150,7 @@ class AbstractScanner<T extends SourceString> implements Scanner {
 
     if (next === $SEMICOLON) {
       appendPrecedenceToken(SEMICOLON_INFO);
+      // Type parameters and arguments cannot contain semicolon.
       discardOpenLt();
       return advance();
     }
@@ -341,6 +349,11 @@ class AbstractScanner<T extends SourceString> implements Scanner {
 
   int tokenizeEquals(int next) {
     // = == ===
+
+    // Type parameters and arguments cannot contain any token that
+    // starts with '='.
+    discardOpenLt();
+
     next = advance();
     if (next === $EQ) {
       return select($EQ, EQ_EQ_EQ_INFO, EQ_EQ_INFO);