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/class_linker-inl.h b/runtime/class_linker-inl.h
index 5198769..87d1c4c 100644
--- a/runtime/class_linker-inl.h
+++ b/runtime/class_linker-inl.h
@@ -17,10 +17,10 @@
 #ifndef ART_RUNTIME_CLASS_LINKER_INL_H_
 #define ART_RUNTIME_CLASS_LINKER_INL_H_
 
+#include "art_field.h"
 #include "class_linker.h"
 #include "gc_root-inl.h"
 #include "gc/heap-inl.h"
-#include "mirror/art_field.h"
 #include "mirror/class_loader.h"
 #include "mirror/dex_cache-inl.h"
 #include "mirror/iftable.h"
@@ -88,7 +88,7 @@
   return resolved_type;
 }
 
-inline mirror::Class* ClassLinker::ResolveType(uint16_t type_idx, mirror::ArtField* referrer) {
+inline mirror::Class* ClassLinker::ResolveType(uint16_t type_idx, ArtField* referrer) {
   mirror::Class* declaring_class = referrer->GetDeclaringClass();
   mirror::DexCache* dex_cache_ptr = declaring_class->GetDexCache();
   mirror::Class* resolved_type = dex_cache_ptr->GetResolvedType(type_idx);
@@ -133,15 +133,19 @@
   return resolved_method;
 }
 
-inline mirror::ArtField* ClassLinker::GetResolvedField(uint32_t field_idx,
-                                                       mirror::Class* field_declaring_class) {
-  return field_declaring_class->GetDexCache()->GetResolvedField(field_idx);
+inline ArtField* ClassLinker::GetResolvedField(uint32_t field_idx, mirror::DexCache* dex_cache) {
+  return dex_cache->GetResolvedField(field_idx, image_pointer_size_);
 }
 
-inline mirror::ArtField* ClassLinker::ResolveField(uint32_t field_idx, mirror::ArtMethod* referrer,
+inline ArtField* ClassLinker::GetResolvedField(
+    uint32_t field_idx, mirror::Class* field_declaring_class) {
+  return GetResolvedField(field_idx, field_declaring_class->GetDexCache());
+}
+
+inline ArtField* ClassLinker::ResolveField(uint32_t field_idx, mirror::ArtMethod* referrer,
                                                    bool is_static) {
   mirror::Class* declaring_class = referrer->GetDeclaringClass();
-  mirror::ArtField* resolved_field = GetResolvedField(field_idx, declaring_class);
+  ArtField* resolved_field = GetResolvedField(field_idx, declaring_class);
   if (UNLIKELY(resolved_field == NULL)) {
     StackHandleScope<2> hs(Thread::Current());
     Handle<mirror::DexCache> dex_cache(hs.NewHandle(declaring_class->GetDexCache()));
@@ -187,17 +191,6 @@
                              ifcount * mirror::IfTable::kMax));
 }
 
-inline mirror::ObjectArray<mirror::ArtField>* ClassLinker::AllocArtFieldArray(Thread* self,
-                                                                              size_t length) {
-  gc::Heap* const heap = Runtime::Current()->GetHeap();
-  // Can't have movable field arrays for mark compact since we need these arrays to always be valid
-  // so that we can do Object::VisitReferences in the case where the fields don't fit in the
-  // reference offsets word.
-  return mirror::ObjectArray<mirror::ArtField>::Alloc(
-      self, GetClassRoot(kJavaLangReflectArtFieldArrayClass), length,
-      kMoveFieldArrays ? heap->GetCurrentAllocator() : heap->GetCurrentNonMovingAllocator());
-}
-
 inline mirror::Class* ClassLinker::GetClassRoot(ClassRoot class_root)
     SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
   DCHECK(!class_roots_.IsNull());