Don't force range of the RangeBoundary::Shl into the Smi.

runtime/vm/intermediate_language.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/intermediate_language.h"
 
 #include "vm/bigint_operations.h"
 #include "vm/bit_vector.h"
 #include "vm/cpu.h"
 #include "vm/dart_entry.h"
@@ skipping 2714 matching lines @@
   ASSERT(value_boundary.IsConstant());
   ASSERT(shift_count >= 0);
   int64_t limit = 64 - shift_count;
   int64_t value = static_cast<int64_t>(value_boundary.ConstantValue());
 
   if ((value == 0) ||
       (shift_count == 0) ||
       ((limit > 0) && (Utils::IsInt(limit, value)))) {
     // Result stays in 64 bit range.
     int64_t result = value << shift_count;
-    return Smi::IsValid(result) ? RangeBoundary(result) : overflow;
+    return RangeBoundary(result);
   }
 
   return overflow;
 }
 
 
 static RangeBoundary CanonicalizeBoundary(const RangeBoundary& a,
                                           const RangeBoundary& overflow) {
   if (a.IsConstant() || a.IsInfinity()) {
     return a;
@@ skipping 1359 matching lines @@
     case Token::kTRUNCDIV: return 0;
     case Token::kMOD: return 1;
     default: UNIMPLEMENTED(); return -1;
   }
 }
 
 
 #undef __
 
 }  // namespace dart