fix(runtime): Do not hide property with more accessors

A property can be defined from both a protocol and a base class. Currently, the protocol definition takes precedence but there are cases in which the other way around is correct.

(ObjCPrototype) Check the property descriptor of the base class and don't define it if the base one has more accessors.
(ObjCClassBuilder) When defining a property check for metadata both with and without considering protocols. Use the one with more accessors.
Add unit tests

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refs #1223

NativeScript / ios-jsc

fix(runtime): Do not hide property with more accessors #1226

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