Remove redundant -ignorewarnings in StackWalkerTest

Change-Id: I16e4fe0e6638826eceb946d979ec1ce2227a6184
diff --git a/src/test/java11/com/android/tools/r8/jdk11/desugaredlibrary/StackWalkerTest.java b/src/test/java11/com/android/tools/r8/jdk11/desugaredlibrary/StackWalkerTest.java
index 94aa61f..280ceb5 100644
--- a/src/test/java11/com/android/tools/r8/jdk11/desugaredlibrary/StackWalkerTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk11/desugaredlibrary/StackWalkerTest.java
@@ -78,8 +78,6 @@
         .addInnerClassesAndStrippedOuter(getClass())
         .addKeepMainRule(Example.class)
         .overrideLibraryFiles(ToolHelper.getAndroidJar(AndroidApiLevel.MAIN))
-        // Missing class java.lang.StackWalker$StackFrame.
-        .addOptionsModification(opt -> opt.ignoreMissingClasses = true)
         .run(parameters.getRuntime(), Example.class)
         .assertSuccessWithOutput(
             compilationSpecification.isProgramShrink() ? EXPECTED_OUTPUT_R8 : EXPECTED_OUTPUT);