Propagate ICData from unoptimized code to instance calls in optimized code.

runtime/vm/isolate.cc

Index: runtime/vm/isolate.cc
===================================================================
--- runtime/vm/isolate.cc	(revision 14215)
+++ runtime/vm/isolate.cc	(working copy)
@@ -311,12 +311,12 @@
 
 ICData* Isolate::GetICDataForDeoptId(intptr_t deopt_id) const {
   if (ic_data_array() == Array::null()) {
-    return NULL;
+    return &ICData::ZoneHandle();
   }
   const Array& array_handle = Array::Handle(ic_data_array());
   if (deopt_id >= array_handle.Length()) {
     // For computations being added in the optimizing compiler.
-    return NULL;
+    return &ICData::ZoneHandle();
   }
   ICData& ic_data_handle = ICData::ZoneHandle();
   ic_data_handle ^= array_handle.At(deopt_id);