Remove KernelDriver/IKG.invalidateAll().

pkg/front_end/lib/src/incremental/kernel_driver.dart

 // Copyright (c) 2017, 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.
 
 import 'dart:async';
 
 import 'package:front_end/file_system.dart';
 import 'package:front_end/src/base/api_signature.dart';
 import 'package:front_end/src/base/performace_logger.dart';
 import 'package:front_end/src/fasta/dill/dill_library_builder.dart';
@@ skipping 147 matching lines @@
   /// file state prior the next invocation of [getKernel] returns the result.
   ///
   /// Invocation of this method will not prevent a [Future] returned from
   /// [getKernel] from completing with a result, but the result is not
   /// guaranteed to be consistent with the new current file state after this
   /// [invalidate] invocation.
   void invalidate(Uri uri) {
     _invalidatedFiles.add(uri);
   }
 
-  /// Flush the current file state completely.
-  ///
-  /// TODO(scheglov) Do we really need this functionality?
-  void invalidateAll() {
-    _invalidatedFiles.addAll(_fsState.fileUris);
-  }
-
   /// Ensure that [dillTarget] includes the [cycle] libraries.  It already
   /// contains all the libraries that sorted before the given [cycle] in
   /// topological order.  Return the result with the cycle libraries.
   Future<LibraryCycleResult> _compileCycle(
       CanonicalName nameRoot, DillTarget dillTarget, LibraryCycle cycle) async {
     return _logger.runAsync('Compile cycle $cycle', () async {
       String signature = _getCycleSignature(cycle);
 
       _logger.writeln('Signature: $signature.');
       var kernelKey = '$signature.kernel';
@@ skipping 182 matching lines @@
 
   LibraryCycleResult(this.cycle, this.signature, this.kernelLibraries);
 }
 
 @visibleForTesting
 class _TestView {
   /// The list of [LibraryCycle]s compiled for the last delta.
   /// It does not include libraries which were read from the cache.
   final List<LibraryCycle> compiledCycles = [];
 }