ObjPtr<>-ify ClassLinker::FindClass(), fix 1 stale reference use.

Thread::CreateAnnotatedStackTrace() was using a stale
reference `aste_array_class`.

Test: m test-art-host-gtest
Test: testrunner.py --host --optimizing
Bug: 31113334
Change-Id: I191907c0053456bb57de425aa6ccd9668df818a2
diff --git a/runtime/interpreter/interpreter_common.cc b/runtime/interpreter/interpreter_common.cc
index fab3509..56658c3 100644
--- a/runtime/interpreter/interpreter_common.cc
+++ b/runtime/interpreter/interpreter_common.cc
@@ -1128,9 +1128,9 @@
 
   StackHandleScope<2> hs(self);
   // Create array for parameter types.
-  ObjPtr<mirror::Class> class_type = mirror::Class::GetJavaLangClass();
   ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
-  ObjPtr<mirror::Class> class_array_type = class_linker->FindArrayClass(self, &class_type);
+  ObjPtr<mirror::Class> class_array_type =
+      GetClassRoot<mirror::ObjectArray<mirror::Class>>(class_linker);
   Handle<mirror::ObjectArray<mirror::Class>> ptypes = hs.NewHandle(
       mirror::ObjectArray<mirror::Class>::Alloc(self,
                                                 class_array_type,