Update test expectation for ProguardMapReaderArgumentsTest

Change-Id: Iac03e41187ea8d4cc9936b68daa827babef6005c
diff --git a/src/test/java/com/android/tools/r8/naming/ProguardMapReaderArgumentsTest.java b/src/test/java/com/android/tools/r8/naming/ProguardMapReaderArgumentsTest.java
index 6c7156d..8e91ae1 100644
--- a/src/test/java/com/android/tools/r8/naming/ProguardMapReaderArgumentsTest.java
+++ b/src/test/java/com/android/tools/r8/naming/ProguardMapReaderArgumentsTest.java
@@ -65,9 +65,6 @@
                     diagnosticMessage(containsString("Could not locate 'id'")),
                     diagnosticPosition(positionLine(4))),
                 allOf(
-                    diagnosticMessage(containsString("Not valid JSON")),
-                    diagnosticPosition(positionLine(6))),
-                allOf(
                     diagnosticMessage(containsString("Could not find a handler for bar")),
                     diagnosticPosition(positionLine(8)))))
         .assertAllInfosMatch(diagnosticType(MappingInformationDiagnostics.class));