Refactor some patching logic

Reduce duplication since app images in-place relocation will require
this code also.

Bug: 22858531
Change-Id: Ibb901b67267e27ef3bc2a0baff77189d4dcd018a
diff --git a/runtime/mirror/array-inl.h b/runtime/mirror/array-inl.h
index ec7d758..b6f424b 100644
--- a/runtime/mirror/array-inl.h
+++ b/runtime/mirror/array-inl.h
@@ -394,6 +394,19 @@
   }
 }
 
+template <typename Visitor>
+inline void PointerArray::Fixup(mirror::PointerArray* dest,
+                                size_t pointer_size,
+                                const Visitor& visitor) {
+  for (size_t i = 0, count = GetLength(); i < count; ++i) {
+    void* ptr = GetElementPtrSize<void*>(i, pointer_size);
+    void* new_ptr = visitor(ptr);
+    if (ptr != new_ptr) {
+      dest->SetElementPtrSize<false, true>(i, new_ptr, pointer_size);
+    }
+  }
+}
+
 }  // namespace mirror
 }  // namespace art