Move ArtField to native

Add linear alloc. Moved ArtField to be native object. Changed image
writer to put ArtFields after the mirror section.

Savings:
2MB on low ram devices
4MB on normal devices

Total PSS measurements before (normal N5, 95s after shell start):
Image size: 7729152 bytes
23112 kB: .NonMoving
23212 kB: .NonMoving
22868 kB: .NonMoving
23072 kB: .NonMoving
22836 kB: .NonMoving
19618 kB: .Zygote
19850 kB: .Zygote
19623 kB: .Zygote
19924 kB: .Zygote
19612 kB: .Zygote
Avg: 42745.4 kB

After:
Image size: 7462912 bytes
17440 kB: .NonMoving
16776 kB: .NonMoving
16804 kB: .NonMoving
17812 kB: .NonMoving
16820 kB: .NonMoving
18788 kB: .Zygote
18856 kB: .Zygote
19064 kB: .Zygote
18841 kB: .Zygote
18629 kB: .Zygote
3499 kB: .LinearAlloc
3408 kB: .LinearAlloc
3424 kB: .LinearAlloc
3600 kB: .LinearAlloc
3436 kB: .LinearAlloc
Avg: 39439.4 kB

No reflection performance changes.

Bug: 19264997
Bug: 17643507

Change-Id: I10c73a37913332080aeb978c7c94713bdfe4fe1c
diff --git a/runtime/mirror/object_array-inl.h b/runtime/mirror/object_array-inl.h
index 80d5135..30bc1cd 100644
--- a/runtime/mirror/object_array-inl.h
+++ b/runtime/mirror/object_array-inl.h
@@ -22,7 +22,6 @@
 #include "array-inl.h"
 #include "base/stringprintf.h"
 #include "gc/heap.h"
-#include "mirror/art_field.h"
 #include "mirror/class.h"
 #include "runtime.h"
 #include "handle_scope-inl.h"
@@ -36,13 +35,13 @@
 inline ObjectArray<T>* ObjectArray<T>::Alloc(Thread* self, Class* object_array_class,
                                              int32_t length, gc::AllocatorType allocator_type) {
   Array* array = Array::Alloc<true>(self, object_array_class, length,
-                                    ComponentSizeShiftWidth<sizeof(HeapReference<Object>)>(),
+                                    ComponentSizeShiftWidth(sizeof(HeapReference<Object>)),
                                     allocator_type);
   if (UNLIKELY(array == nullptr)) {
     return nullptr;
   } else {
     DCHECK_EQ(array->GetClass()->GetComponentSizeShift(),
-              ComponentSizeShiftWidth<sizeof(HeapReference<Object>)>());
+              ComponentSizeShiftWidth(sizeof(HeapReference<Object>)));
     return array->AsObjectArray<T>();
   }
 }