Fix VIXL assembler test for heap-poisoning configurations.

And fix a typo in test name.

Test: ART_HEAP_POISONING=true m test-art-host-gtest-assembler_thumb_test
Change-Id: Ibc3750676aa7a7b23c93ee0babb8d9c207cb762a
diff --git a/compiler/utils/arm/jni_macro_assembler_arm_vixl.h b/compiler/utils/arm/jni_macro_assembler_arm_vixl.h
index dfc35b7..9fc683d 100644
--- a/compiler/utils/arm/jni_macro_assembler_arm_vixl.h
+++ b/compiler/utils/arm/jni_macro_assembler_arm_vixl.h
@@ -215,8 +215,8 @@
   // List of exception blocks to generate at the end of the code cache.
   ArenaVector<std::unique_ptr<ArmVIXLJNIMacroAssembler::ArmException>> exception_blocks_;
   // Used for testing.
-  friend class ArmVIXAssemblerTest_VixlLoadFromOffset_Test;
-  friend class ArmVIXAssemblerTest_VixlStoreToOffset_Test;
+  friend class ArmVIXLAssemblerTest_VixlLoadFromOffset_Test;
+  friend class ArmVIXLAssemblerTest_VixlStoreToOffset_Test;
 };
 
 }  // namespace arm