add support for native methods in class

pkg/front_end/lib/src/fasta/parser/parser.dart

Index: pkg/front_end/lib/src/fasta/parser/parser.dart
diff --git a/pkg/front_end/lib/src/fasta/parser/parser.dart b/pkg/front_end/lib/src/fasta/parser/parser.dart
index d3bcceae05a50ab1bdd7ec486e4fa479814c7fa3..365aa3bc9c02124138837225ae60f581e0643b39 100644
--- a/pkg/front_end/lib/src/fasta/parser/parser.dart
+++ b/pkg/front_end/lib/src/fasta/parser/parser.dart
@@ -2406,6 +2406,13 @@ class Parser {
             ? MemberKind.StaticMethod
             : MemberKind.NonStaticMethod);
     token = parseInitializersOpt(token);
+
+    Token nativeToken;
+    if (optional('native', token)) {
+      nativeToken = token;
+      token = parseNativeClause(nativeToken);

[ahe, 2017/08/25 09:05:40]

I think the problem is how functions bodies are being skipped in
ClassMemberParser (and thus DietParser). 

If I'm right, the solution should be to move this logic to parseFunctionBody and
update skipFunctionBody to generate the native event.

+    }
+
     AsyncModifier savedAsyncModifier = asyncState;
     Token asyncToken = token;
     token = parseAsyncModifier(token);
@@ -2416,10 +2423,14 @@ class Parser {
       token = parseRedirectingFactoryBody(token);
     } else {
       token = parseFunctionBody(
-          token, false, staticModifier == null || externalModifier != null);
+          token,
+          false,
+          staticModifier == null ||
+              externalModifier != null ||
+              nativeToken != null);
     }
     asyncState = savedAsyncModifier;
-    listener.endMethod(getOrSet, start, token);
+    listener.endMethod(getOrSet, start, nativeToken, token);
     return token.next;
   }