The main logic of the `InheritDefinitionFeature` is to go through the prototype chain of a given Component and merge all Angular-specific information onto that Component def. The problem happens in case there is a Component in a hierarchy that also contains the `InheritDefinitionFeature` (i.e. it extends some other Component), so it inherits all Angular-specific information from its super class. As a result, the root Component may end up having duplicate information inherited from different Components in hierarchy.
Let's consider the following structure: `GrandChild` extends `Child` that extends `Base` and the `Base` class has a `HostListener`. In this scenario `GrandChild` and `Child` will have `InheritDefinitionFeature` included into the `features` list. The processing will happend in the following order:
- `Child` inherits `HostListener` from the `Base` class
- `GrandChild` inherits `HostListener` from the `Child` class
- since `Child` has a parent, `GrandChild` also inherits from the `Base` class
The result is that the `GrandChild` def has duplicated host listener, which is not correct.
This commit introduces additional logic that checks whether we came across a def that has `InheritDefinitionFeature` feature (which means that this def already inherited information from its super classes). If that's the case, we skip further fields-related inheritance logic, but keep going though the prototype chain to look for super classes that contain other features (like NgOnChanges), that we need to invoke for a given Component def.
PR Close#34244
effb92dfae