Fix for issue 1399 (and minor error message clean-up)

compiler/java/com/google/dart/compiler/parser/AbstractParser.java

Index: compiler/java/com/google/dart/compiler/parser/AbstractParser.java
===================================================================
--- compiler/java/com/google/dart/compiler/parser/AbstractParser.java	(revision 8308)
+++ compiler/java/com/google/dart/compiler/parser/AbstractParser.java	(working copy)
@@ -145,6 +145,11 @@
     return true;
   }
 
+  protected Location peekTokenLocation(int n) {
+    assert (n >= 0);
+    return ctx.peekTokenLocation(n);
+  }
+
   protected String getPeekTokenValue(int n) {
     assert (n >= 0);
     String value = ctx.peekTokenString(n);