Include declaration origin in testData.

compiler/testData/ir/irText/expressions/augmentedAssignment2.txt

@@ -15,10 +15,10 @@ FILE /augmentedAssignment2.kt
   FUN public operator fun A.modAssign(s: kotlin.String): kotlin.Unit
     BLOCK_BODY
   PROPERTY public val p: A
-    FIELD public val p: A
+    FIELD PROPERTY_BACKING_FIELD public val p: A
       EXPRESSION_BODY
         CALL 'constructor A()' type=A operator=null
-    FUN public fun <get-p>(): A
+    FUN DEFAULT_PROPERTY_ACCESSOR public fun <get-p>(): A
       BLOCK_BODY
         RETURN type=kotlin.Nothing from='<get-p>(): A'
           GET_BACKING_FIELD 'p: A' type=A operator=null