Support FrameLookup vm test on ARM, requiring among other things:

runtime/vm/simulator_mips.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.
 
 // Declares a Simulator for MIPS instructions if we are not generating a native
 // MIPS binary. This Simulator allows us to run and debug MIPS code generation
 // on regular desktop machines.
 // Dart calls into generated code by "calling" the InvokeDartCode stub,
 // which will start execution in the Simulator or forwards to the real entry
 // on a MIPS HW platform.
@@ skipping 37 matching lines @@
 
   // Accessors for hi, lo registers.
   void set_hi_register(int32_t value) { hi_reg_ = value; }
   void set_lo_register(int32_t value) { lo_reg_ = value; }
   int32_t get_hi_register() const { return hi_reg_; }
   int32_t get_lo_register() const { return lo_reg_; }
 
   // Accessor to the internal simulator stack top.
   uword StackTop() const;
 
+  // The isolate's top_exit_frame_info refers to a Dart frame in the simulator
+  // stack. The simulator's top_exit_frame_info refers to a C++ frame in the
+  // native stack.
+  uword top_exit_frame_info() const { return top_exit_frame_info_; }
+  void set_top_exit_frame_info(uword value) { top_exit_frame_info_ = value; }
+
   // Call on program start.
   static void InitOnce();
 
   // Dart generally calls into generated code with 5 parameters. This is a
   // convenience function, which sets up the simulator state and grabs the
   // result on return.
   int64_t Call(int32_t entry,
                int32_t parameter0,
                int32_t parameter1,
                int32_t parameter2,
@@ skipping 20 matching lines @@
 
   int32_t registers_[kNumberOfCpuRegisters];
   double fregisters_[kNumberOfFRegisters];
   uword pc_;
 
   // Simulator support.
   char* stack_;
   int icount_;
   bool delay_slot_;
   SimulatorSetjmpBuffer* last_setjmp_buffer_;
+  uword top_exit_frame_info_;
 
   // Registered breakpoints.
   Instr* break_pc_;
   int32_t break_instr_;
 
   // Illegal memory access support.
   static bool IsIllegalAddress(uword addr) {
     return addr < 64*1024;
   }
   void HandleIllegalAccess(uword addr, Instr* instr);
@@ skipping 42 matching lines @@
     last_setjmp_buffer_ = buffer;
   }
 
   friend class SimulatorDebugger;
   friend class SimulatorSetjmpBuffer;
 };
 
 }  // namespace dart
 
 #endif  // VM_SIMULATOR_MIPS_H_