JVM IR: change generation scheme of property $delegate methods

Generate $delegate method as instance method in
PropertyReferenceDelegationLowering, and remove dispatch receiver later
in MakePropertyDelegateMethodsStatic. The method needs to be static to
be non-overridable (see delegateMethodIsNonOverridable.kt), and public
to be accessible in reflection.

Otherwise we generated incorrect IR where a static function accessed an
instance field of the containing class, which failed in multiple places
including LocalDeclarationsLowering.

 #KT-48350 Fixed

compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/LocalDeclarationsLowering.kt

@@ -185,7 +185,8 @@ class LocalDeclarationsLowering(
         override fun irGet(startOffset: Int, endOffset: Int, valueDeclaration: IrValueDeclaration): IrExpression? {
             val field = classContext.capturedValueToField[valueDeclaration] ?: return null
 
-            val receiver = member.dispatchReceiverParameter!!
+            val receiver = member.dispatchReceiverParameter
+                ?: error("No dispatch receiver parameter for ${member.render()}")
             return IrGetFieldImpl(
                 startOffset, endOffset, field.symbol, field.type,
                 receiver = IrGetValueImpl(startOffset, endOffset, receiver.type, receiver.symbol)