Disable string interpolation optimization until fixed.

runtime/vm/flow_graph_optimizer.cc

 // 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.
 
 #include "vm/flow_graph_optimizer.h"
 
 #include "vm/bit_vector.h"
 #include "vm/cha.h"
 #include "vm/dart_entry.h"
 #include "vm/flow_graph_builder.h"
@@ skipping 6017 matching lines @@
 }
 
 
 void ConstantPropagator::VisitPolymorphicInstanceCall(
     PolymorphicInstanceCallInstr* instr) {
   SetValue(instr, non_constant_);
 }
 
 
 void ConstantPropagator::VisitStaticCall(StaticCallInstr* instr) {
+  SetValue(instr, non_constant_);
+  return;
+  // TODO(srdjan): Enable code below once issues resolved.
   if (IsNonConstant(instr->constant_value())) {
     // Do not bother with costly analysis if we already know that the
     // instruction is not a constant.
     SetValue(instr, non_constant_);
     return;
   }
   MethodRecognizer::Kind recognized_kind =
       MethodRecognizer::RecognizeKind(instr->function());
   if (recognized_kind == MethodRecognizer::kStringBaseInterpolate) {
     // static String _interpolate(List values)
@@ skipping 1704 matching lines @@
   }
 
   // Insert materializations at environment uses.
   for (intptr_t i = 0; i < exits.length(); i++) {
     CreateMaterializationAt(exits[i], alloc, alloc->cls(), *fields);
   }
 }
 
 
 }  // namespace dart