Don't require eliminating certain type checks in unoptimized compilation.

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/cpu.h"
 #include "vm/dart_entry.h"
@@ skipping 26 matching lines @@
 DEFINE_FLAG(bool, remove_redundant_phis, true, "Remove redundant phis.");
 DEFINE_FLAG(bool, trace_constant_propagation, false,
     "Print constant propagation and useless code elimination.");
 DEFINE_FLAG(bool, trace_load_optimization, false,
     "Print live sets for load optimization pass.");
 DEFINE_FLAG(bool, trace_optimization, false, "Print optimization details.");
 DEFINE_FLAG(bool, trace_range_analysis, false, "Trace range analysis progress");
 DEFINE_FLAG(bool, truncating_left_shift, true,
     "Optimize left shift to truncate if possible");
 DEFINE_FLAG(bool, use_cha, true, "Use class hierarchy analysis.");
-DECLARE_FLAG(bool, eliminate_type_checks);
 DECLARE_FLAG(bool, enable_type_checks);
 DECLARE_FLAG(bool, source_lines);
 DECLARE_FLAG(bool, trace_type_check_elimination);
 DECLARE_FLAG(bool, warn_on_javascript_compatibility);
 
 
 static bool ShouldInlineSimd() {
   return FlowGraphCompiler::SupportsUnboxedSimd128();
 }
 
@@ skipping 9788 matching lines @@
   }
 
   // Insert materializations at environment uses.
   for (intptr_t i = 0; i < exits.length(); i++) {
     CreateMaterializationAt(exits[i], alloc, alloc->cls(), *slots);
   }
 }
 
 
 }  // namespace dart