Fix test checking changed diagnostic

Change-Id: I039041171d9647c90c9a00790b8ba8eca1101e75
diff --git a/src/test/java/com/android/tools/r8/classlookup/LibraryClassExtendsProgramClassTest.java b/src/test/java/com/android/tools/r8/classlookup/LibraryClassExtendsProgramClassTest.java
index dff913e..b2f9eae 100644
--- a/src/test/java/com/android/tools/r8/classlookup/LibraryClassExtendsProgramClassTest.java
+++ b/src/test/java/com/android/tools/r8/classlookup/LibraryClassExtendsProgramClassTest.java
@@ -102,7 +102,9 @@
     Builder<String> builder = ImmutableSet.builder();
     for (String libraryClass : libraryClassesExtendingTestCase) {
       builder.add(
-          "Library class " + libraryClass + " extends program class junit.framework.TestCase");
+          "Library class "
+              + libraryClass
+              + " extends program class junit.framework.TestCase (origin: <unknown>)");
     }
     Set<String> expected = builder.build();
     for (Diagnostic diagnostic : diagnostics) {