ObjPtr<>-ify DexCache.

Test: m test-art-host-gtest
Test: testrunner.py --host --optimizing
Bug: 31113334
Change-Id: Ic4747928255afca61aca6802e7fec0585c6c1226
diff --git a/runtime/jni/java_vm_ext.cc b/runtime/jni/java_vm_ext.cc
index 370a456..1bf88c5 100644
--- a/runtime/jni/java_vm_ext.cc
+++ b/runtime/jni/java_vm_ext.cc
@@ -38,6 +38,7 @@
 #include "jni_internal.h"
 #include "mirror/class-inl.h"
 #include "mirror/class_loader.h"
+#include "mirror/dex_cache-inl.h"
 #include "nativebridge/native_bridge.h"
 #include "nativehelper/scoped_local_ref.h"
 #include "nativehelper/scoped_utf_chars.h"