ARM & MIPS: Try to use the object pool before trying to embed a pointer, like ARM64 and X64.

runtime/vm/assembler_arm.h

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #ifndef VM_ASSEMBLER_ARM_H_
 #define VM_ASSEMBLER_ARM_H_
 
 #ifndef VM_ASSEMBLER_H_
 #error Do not include assembler_arm.h directly; use assembler.h instead.
 #endif
@@ skipping 742 matching lines @@
                     Label* miss);
 
   void UpdateRangeFeedback(Register value,
                            intptr_t idx,
                            Register ic_data,
                            Register scratch1,
                            Register scratch2,
                            Label* miss);
 
   intptr_t FindImmediate(int32_t imm);
+  bool CanLoadFromObjectPool(const Object& object) const;
   void LoadFromOffset(OperandSize type,
                       Register reg,
                       Register base,
                       int32_t offset,
                       Condition cond = AL);
   void LoadFieldFromOffset(OperandSize type,
                            Register reg,
                            Register base,
                            int32_t offset,
                            Condition cond = AL) {
@@ skipping 376 matching lines @@
                      Register new_value,
                      FieldContent old_content);
 
   DISALLOW_ALLOCATION();
   DISALLOW_COPY_AND_ASSIGN(Assembler);
 };
 
 }  // namespace dart
 
 #endif  // VM_ASSEMBLER_ARM_H_