Add a typeannotation and a missing argument to remove warnings.

lib/compiler/implementation/ssa/nodes.dart

 // Copyright (c) 2012, 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.
 
 interface HVisitor<R> {
   R visitAdd(HAdd node);
   R visitBitAnd(HBitAnd node);
   R visitBitNot(HBitNot node);
   R visitBitOr(HBitOr node);
   R visitBitXor(HBitXor node);
@@ skipping 1558 matching lines @@
 class HShiftLeft extends HBinaryBitOp {
   HShiftLeft(HStatic target, HInstruction left, HInstruction right)
       : super(target, left, right);
   accept(HVisitor visitor) => visitor.visitShiftLeft(this);
 
   // Shift left cannot be mapped to the native operator unless the
   // shift count is guaranteed to be an integer in the [0,31] range.
   bool get builtin() {
     if (!left.isInteger() || !right.isConstantInteger()) return false;
     HConstant rightConstant = right;
-    int count = rightConstant.constant.value;
+    IntConstant intConstant = rightConstant.constant;
+    int count = intConstant.value;
     return count >= 0 && count <= 31;
   }
 
   ShiftLeftOperation get operation() => const ShiftLeftOperation();
   int typeCode() => 11;
   bool typeEquals(other) => other is HShiftLeft;
   bool dataEquals(HInstruction other) => true;
 }
 
 class HShiftRight extends HBinaryBitOp {
@@ skipping 1040 matching lines @@
   HBasicBlock get start() => expression.start;
   HBasicBlock get end() {
     // We don't create a switch block if there are no cases.
     assert(!statements.isEmpty());
     return statements.last().end;
   }
 
   bool accept(HStatementInformationVisitor visitor) =>
       visitor.visitSwitchInfo(this);
 }