Fix `CanUseKnownBootImageVarHandle()`, part 2.

(cherry picked from commit c05a32a746812f16914958bf8769cb6537d3af40)

Test: Rely on TreeHugger.
Bug: 191765508
Bug: 230729606
Merged-In: I1955b542cb7c28378aa588cd16e66eb5ffc33c8a
Change-Id: Ib72a2a6516c7a06758abb63a7d281b2f396fe691
diff --git a/compiler/optimizing/instruction_simplifier.cc b/compiler/optimizing/instruction_simplifier.cc
index 4db258b..789f077 100644
--- a/compiler/optimizing/instruction_simplifier.cc
+++ b/compiler/optimizing/instruction_simplifier.cc
@@ -2940,7 +2940,7 @@
     DCHECK(!declaring_class->IsInitialized());
     return false;
   }
-  HInstruction* load_class = var_handle_instruction->InputAt(0)->AsLoadClass();
+  HInstruction* load_class = var_handle_instruction->InputAt(0);
   if (kIsDebugBuild) {
     bool is_in_boot_image = false;
     if (Runtime::Current()->GetHeap()->ObjectIsInBootImageSpace(declaring_class)) {