Address some comments and clean up

Change-Id: I538cf204f1c89d5fc81f8fc5e5800fcf1cf87359
diff --git a/compiler/image_writer.cc b/compiler/image_writer.cc
index 17d75a3..953b1de 100644
--- a/compiler/image_writer.cc
+++ b/compiler/image_writer.cc
@@ -719,7 +719,7 @@
     }
     // InternImageString allows us to intern while holding the heap bitmap lock. This is safe since
     // we are guaranteed to not have GC during image writing.
-    mirror::String* const interned = Runtime::Current()->GetInternTable()->InternImageString(
+    mirror::String* const interned = Runtime::Current()->GetInternTable()->InternStrongImageString(
         obj->AsString());
     if (obj != interned) {
       if (!IsImageBinSlotAssigned(interned)) {