leaving the name for field defs

so we can reuse that expression
so we can highlight it in the debugger

test/cases/class_definition/class_ops.tst

@@ -14,7 +14,8 @@ s(:statements,
         s(:parameters,
           s(:parameter, :Integer, :x)),
         s(:statements,
-          s(:field_def, :Integer, :abba,
+          s(:field_def, :Integer,
+            s(:name, :abba),
             s(:int, 5)),
           s(:return,
             s(:operator_value, :+,

test/cases/function_definition/function_foo2.tst

@@ -9,7 +9,8 @@ s(:statements,
     s(:parameters,
       s(:parameter, :Integer, :x)),
     s(:statements,
-      s(:field_def, :Integer, :a,
+      s(:field_def, :Integer,
+        s(:name, :a),
         s(:int, 5)),
       s(:return,
         s(:name, :a)))))

test/cases/function_definition/function_ops.tst

@@ -9,7 +9,8 @@ s(:statements,
     s(:parameters,
       s(:parameter, :Integer, :x)),
     s(:statements,
-      s(:field_def, :Integer, :abba,
+      s(:field_def, :Integer,
+        s(:name, :abba),
         s(:int, 5)),
       s(:assignment,
         s(:name, :abba),

test/cases/function_definition/function_return.tst

@@ -9,7 +9,8 @@ s(:statements,
     s(:parameters,
       s(:parameter, :Object, :n)),
     s(:statements,
-      s(:field_def, :Integer, :i,
+      s(:field_def, :Integer,
+        s(:name, :i),
         s(:field_access,
           s(:receiver,
             s(:name, :n)),