Consider support for extending native generic classes and providing generic arguments

Currently, there is no way to implement for example java.util.List<T> and provide information what would be the type T. When extending such class/interface from TypeScript the following way:

@Interfaces([java.util.List])
class JSList implements java.util.List {
}

the static binding generator prior 5.3.1 would generate a proxy class with a similar signature:
public class JSList implements java.util.List
The introduced changes of the SBG in 5.3.1 generate public class JSList implements java.util.List<Object> having resolved the generic parameter T using its erasure (in this case java.lang.Object) as if it's a raw class inheritance.

With the changes of the SBG in 5.3.1, there is a way to feed it information about what would be the generic parameters when extending, however this would require some changes in the syntax of extending/implementing native classes:

@Native
class JSList implements java.util.List<java.lang.Integer>{
}

The above shown syntax would be possible with some changes in the webpack plugin and the js_parser.js in the SBG.
In order to collect information about the generic arguments provided in the TS code there should be a custom transformer plugged into the webpack pipeline whose goal would be to lookup every TS node with a @Native decorator and preserve its extended class and implemented interfaces information somewhere. This could be stored by modifying the AST and creating internal decorators only for storage. Further, when the js_parser.js parses the JS code, it can look for the internal decorators and retrieve the information about the generics storing them for the SBG.

Issueで説明されている webpack plugin と js_parser.js から始めます。@Native 宣言と、現在の拡張型または実装型がどのように表現されているかを追跡し、その後、カスタム transformer が parser のためにジェネリック引数を保持する方法を確認します。TypeScript の java.util.List<java.lang.Integer> のようなコードが、Object ではなくそのジェネリック引数を持つ binding を生成すれば完了です。