refactor(change_detection): made ChangeDetector and ProtoChangeDetector interfaces

List of changes:

- Makes ChangeDetector and ProtoChangeDetector interfaces
- Assigns a unique id to every detector

modules/benchmarks/src/change_detection/change_detection_benchmark.ts

@@ -379,7 +379,7 @@ class FakeDirectives {
   getDirectiveFor(record) { return this.targetObj; }
 }
 
-class DummyDispatcher extends ChangeDispatcher {
+class DummyDispatcher implements ChangeDispatcher {
   notifyOnBinding(bindingRecord, newValue) { throw "Should not be used"; }
   notifyOnAllChangesDone() {}
 }