Add type annotations to remove warnings and fix a bug.

lib/compiler/implementation/ssa/value_range_analyzer.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.
 
 /**
  * A [Value] represents both symbolic values like the value of a
  * parameter, or the length of an array, and concrete values, like
  * constants.
  */
 abstract class Value {
@@ skipping 635 matching lines @@
     }
 
     return indexRange;
   }
 
   Range visitRelational(HRelational relational) {
     HInstruction right = relational.right;
     HInstruction left = relational.left;
     if (!left.isInteger(types)) return const Range.unbound();
     if (!right.isInteger(types)) return const Range.unbound();
-    Operation operation = relational.operation(constantSystem);
+    BinaryOperation operation = relational.operation(constantSystem);
     Range rightRange = ranges[relational.right];
     Range leftRange = ranges[relational.left];
 
     if (relational is HEquals || relational is HIdentity) {
       handleEqualityCheck(relational);
     } else if (operation.apply(leftRange, rightRange)) {
       relational.block.rewrite(
           relational, graph.addConstantBool(true, constantSystem));
       relational.block.remove(relational);
     } else if (reverseOperation(operation).apply(leftRange, rightRange)) {
@@ skipping 68 matching lines @@
     cursor.block.addBefore(cursor, newInstruction);
     // Update the users of the instruction dominated by [cursor] to
     // use the new instruction, that has an narrower range.
     Set<HInstruction> dominatedUsers = instruction.dominatedUsers(cursor);
     for (HInstruction user in dominatedUsers) {
       user.changeUse(instruction, newInstruction);
     }
     return newInstruction;
   }
 
-  static Operation reverseOperation(BinaryOperation operation) {
+  static BinaryOperation reverseOperation(BinaryOperation operation) {
     if (operation == const LessOperation()) {
       return const GreaterEqualOperation();
     } else if (operation == const LessEqualOperation()) {
       return const GreaterOperation();
     } else if (operation == const GreaterOperation()) {
       return const LessEqualOperation();
     } else if (operation == const GreaterEqualOperation()) {
       return const LessOperation();
     } else {
       return null;
@@ skipping 181 matching lines @@
     if (instruction is HPhi && !instruction.block.isLoopHeader()) {
       HInstruction result = unwrap(instruction.inputs[0]);
       for (int i = 1; i < instruction.inputs.length; i++) {
         if (result != unwrap(instruction.inputs[i])) return instruction;
       }
       return result;
     }
     return instruction;
   }
 }