Always return identifier from handleElementRename() (KT-14358)

Returning reference will lead to replacing identifier with reference, that result bad psi, bad stubs, and failure at some point.

 #KT-14358 Fixed

plugins/android-extensions/android-extensions-idea/src/org/jetbrains/kotlin/android/synthetic/idea/AndroidSimpleNameReferenceExtension.kt

@@ -49,9 +49,9 @@ class AndroidSimpleNameReferenceExtension : SimpleNameReferenceExtension {
         }
         else if (isLayoutPackageIdentifier(reference)) {
             return if (newElementName.endsWith(".xml"))
-                psiFactory.createSimpleName(newElementName.dropLast(".xml".length))
+                psiFactory.createSimpleName(newElementName.dropLast(".xml".length)).getIdentifier()
             else
-                reference.element
+                reference.element.getIdentifier()
         }
 
         return null