Change FieldHelper to use a handle.

Fixed compaction bugs related to FieldHelper::GetType in:
artSet32InstanceFromCode
SetFieldValueImpl
CheckReceiver
Field_set
interpreter::DoFieldPut
MethodVerifier::VerifyISGet
MethodVerifier::VerifyISPut
MethodVerifier::VerifyIGetQuick

Bug: 13077697

Change-Id: I7de9ded2893b5568d43e4daa86fd135bf5508b72
diff --git a/runtime/mirror/object.h b/runtime/mirror/object.h
index 442909d..f0c5a73 100644
--- a/runtime/mirror/object.h
+++ b/runtime/mirror/object.h
@@ -316,6 +316,7 @@
 
  private:
   // Verify the type correctness of stores to fields.
+  // TODO: This can cause thread suspension and isn't moving GC safe.
   void CheckFieldAssignmentImpl(MemberOffset field_offset, Object* new_value)
       SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
   void CheckFieldAssignment(MemberOffset field_offset, Object* new_value)