Cleanup 1: split parts into their own libraries, remove unused imports

pkg/compiler/lib/src/ssa/validate.dart

 // Copyright (c) 2011, 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.
 
-part of ssa;
+

[sra1, 2016/03/04 01:21:10]

extra line

[Siggi Cherem (dart-lang), 2016/03/14 21:05:29]

Done.

+import 'nodes.dart';
 
 class HValidator extends HInstructionVisitor {
   bool isValid = true;
   HGraph graph;
 
   void visitGraph(HGraph visitee) {
     graph = visitee;
     visitDominatorTree(visitee);
   }
 
@@ skipping 175 matching lines @@
       markInvalid("Instruction in wrong block");
     }
     if (!hasCorrectInputs()) {
       markInvalid("Incorrect inputs");
     }
     if (!hasCorrectUses()) {
       markInvalid("Incorrect uses");
     }
   }
 }