Revert "Add support for the new function-type syntax."

pkg/front_end/lib/src/fasta/source/diet_listener.dart

Index: pkg/front_end/lib/src/fasta/source/diet_listener.dart
diff --git a/pkg/front_end/lib/src/fasta/source/diet_listener.dart b/pkg/front_end/lib/src/fasta/source/diet_listener.dart
index e8029aa91db1749ae57949200bc678bc54359afd..4b4f7f116c0ae89e6df9c83bb9fa9fc27b059dd0 100644
--- a/pkg/front_end/lib/src/fasta/source/diet_listener.dart
+++ b/pkg/front_end/lib/src/fasta/source/diet_listener.dart
@@ -133,7 +133,7 @@ class DietListener extends StackListener {
   }
 
   @override
-  void handleType(Token beginToken, Token endToken) {
+  void endType(Token beginToken, Token endToken) {
     debugEvent("Type");
     discard(1);
   }
@@ -190,8 +190,7 @@ class DietListener extends StackListener {
   }
 
   @override
-  void endFunctionTypeAlias(
-       Token typedefKeyword, Token equals, Token endToken) {
+  void endFunctionTypeAlias(Token typedefKeyword, Token endToken) {
     debugEvent("FunctionTypeAlias");
     discard(2); // Name + endToken.
     checkEmpty(typedefKeyword.charOffset);