Added test with constant in class object.

jps-plugin/testData/incremental/classObjectConstantChanged/const.kt

@@ -0,0 +1,8 @@
+package test
+
+class Klass {
+    class object {
+        // Old and new constant values are different, but their hashes are the same
+        val CONST = "BF"
+    }
+}