Delete CPS IR

pkg/compiler/lib/src/tree_ir/optimization/optimization.dart

Index: pkg/compiler/lib/src/tree_ir/optimization/optimization.dart
diff --git a/pkg/compiler/lib/src/tree_ir/optimization/optimization.dart b/pkg/compiler/lib/src/tree_ir/optimization/optimization.dart
deleted file mode 100644
index ebf201a3a0bd51377c95858298f3b622e237df38..0000000000000000000000000000000000000000
--- a/pkg/compiler/lib/src/tree_ir/optimization/optimization.dart
+++ /dev/null
@@ -1,17 +0,0 @@
-library tree_ir.optimization;
-
-import '../tree_ir_nodes.dart';
-
-export 'logical_rewriter.dart' show LogicalRewriter;
-export 'loop_rewriter.dart' show LoopRewriter;
-export 'pull_into_initializers.dart' show PullIntoInitializers;
-export 'statement_rewriter.dart' show StatementRewriter;
-export 'variable_merger.dart' show VariableMerger;
-
-/// An optimization pass over the Tree IR.
-abstract class Pass {
-  /// Applies optimizations to root, rewriting it in the process.
-  void rewrite(FunctionDefinition root);
-
-  String get passName;
-}