refactor(ivy): don't include removed classes in the styling debug (#34375)

This is mostly done to allign behaviour with DebugElement.classes and remove
Proxy usage (not supported in IE10/11).

PR Close #34375

packages/core/test/acceptance/styling_spec.ts

@@ -1212,8 +1212,7 @@ describe('styling', () => {
 
         classesSummary = classes.summary;
         abcSummary = classesSummary['abc'];
-        expect(abcSummary.prop).toEqual('abc');
-        expect(abcSummary.value).toBeFalsy();
+        expect(abcSummary).toBeUndefined();
 
         let defSummary = classesSummary['def'];
         expect(defSummary.prop).toEqual('def');