Implement missing features to run Hello world! on simulated ARM.

runtime/vm/dart.cc

Index: runtime/vm/dart.cc
===================================================================
--- runtime/vm/dart.cc	(revision 21565)
+++ runtime/vm/dart.cc	(working copy)
@@ -220,8 +220,10 @@
   Object::VerifyBuiltinVtables();
 
   StubCode::Init(isolate);
-  // TODO(regis): Reenable this code for arm and mips when possible.
-#if defined(TARGET_ARCH_IA32) || defined(TARGET_ARCH_X64)
+  // TODO(regis): Reenable this code for mips when possible.
+#if defined(TARGET_ARCH_IA32) ||                                               \
+    defined(TARGET_ARCH_X64) ||                                                \
+    defined(TARGET_ARCH_ARM)
   isolate->megamorphic_cache_table()->InitMissHandler();
 #endif
   if (FLAG_heap_trace) {