Create from Usage: Place extension properties after the usage and generate stub getter

#KT-11795 Fixed

idea/testData/quickfix/createFromUsage/createVariable/property/valOnLibObject.kt.after

@@ -1,9 +1,11 @@
 // "Create extension property 'Unit.foo'" "true"
-// ERROR: Property must be initialized
 // WITH_RUNTIME
 
-private val Unit.foo: Int
-
 fun test() {
     val a: Int = Unit.foo
 }
+
+private val Unit.foo: Int
+    get() {
+        TODO("not implemented") //To change body of created functions use File | Settings | File Templates.
+    }