Compile and simulate first dart function on arm generated from ast.

runtime/vm/simulator_mips.h

Index: runtime/vm/simulator_mips.h
===================================================================
--- runtime/vm/simulator_mips.h	(revision 19151)
+++ runtime/vm/simulator_mips.h	(working copy)
@@ -20,6 +20,8 @@
 
 class Simulator {
  public:
+  static const uword kSimulatorStackUnderflowSize = 64;
+
   Simulator();
   ~Simulator();
 
@@ -27,6 +29,9 @@
   // current isolate
   static Simulator* Current();
 
+  // Accessor to the internal simulator stack top.
+  uword StackTop() const;
+
   // Call on program start.
   static void InitOnce();
 
@@ -39,6 +44,9 @@
                int32_t parameter2,
                int32_t parameter3,
                int32_t parameter4);
+
+ private:
+  char* stack_;
 };
 
 }  // namespace dart