Rework Objective-C constructors and support 'initBy' intrinsic

Interop/Runtime/src/native/kotlin/kotlinx/cinterop/ObjectiveCImpl.kt

@@ -51,8 +51,17 @@ class ObjCPointerHolder(inline val rawPtr: NativePtr) {
 @konan.internal.ExportForCompiler
 private external fun ObjCObject.initFromPtr(ptr: NativePtr)
 
+@konan.internal.Intrinsic
+external fun <T : ObjCObjectBase> T.initBy(constructorCall: T): T
+
 @konan.internal.ExportForCompiler
-private fun ObjCObject.initFrom(other: ObjCObject?) = this.initFromPtr(other!!.rawPtr)
+private fun ObjCObjectBase.superInitCheck(superInitCallResult: ObjCObject?) {
+    if (superInitCallResult == null)
+        throw RuntimeException("Super initialization failed")
+
+    if (superInitCallResult.rawPtr != this.rawPtr)
+        throw UnsupportedOperationException("Super initializer has replaced object")
+}
 
 fun <T : Any?> Any?.uncheckedCast(): T = @Suppress("UNCHECKED_CAST") (this as T) // TODO: make private
 

Interop/StubGenerator/src/main/kotlin/org/jetbrains/kotlin/native/interop/gen/ObjCStubs.kt

@@ -421,7 +421,7 @@ val ObjCClassOrProtocol.kotlinName: String get() = when (this) {
 }
 
 private val ObjCClass.baseClassName: String
-    get() = baseClass?.name ?: "ObjCObject"
+    get() = baseClass?.name ?: "ObjCObjectBase"
 
 private fun Parameter.getTypeStringRepresentation() =
         (if (this.nsConsumed) "__attribute__((ns_consumed)) " else "") + type.getStringRepresentation()