Move frog/leg to lib/compiler/implementation.

lib/compiler/implementation/leg.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.
 
 #library('leg');
 
-#import('../../lib/uri/uri.dart');
+#import('../../uri/uri.dart');
 
 #import('colors.dart');
 #import('elements/elements.dart');
 #import('native_handler.dart', prefix: 'native');
 #import('scanner/scanner_implementation.dart');
 #import('scanner/scannerlib.dart');
 #import('ssa/ssa.dart');
 #import('string_validator.dart');
 #import('tree/tree.dart');
 #import('util/characters.dart');
@@ skipping 10 matching lines @@
 #source('resolver.dart');
 #source('script.dart');
 #source('tree_validator.dart');
 #source('typechecker.dart');
 #source('universe.dart');
 #source('warnings.dart');
 
 void unreachable() {
   throw const Exception("Internal Error (Leg): UNREACHABLE");
 }