Use list_dart_files.py instead of list_files.py in GN build.

utils/dartanalyzer/BUILD.gn

 # Copyright (c) 2016, 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("../invoke_dart.gni")
 
 group("dartanalyzer") {
   deps = [
     ":generate_dartanalyzer_snapshot",
     ":generate_summary_spec",
     ":generate_summary_strong",
   ]
 }
 
-analyzer_files = exec_script("../../tools/list_files.py",
-                             ["\\.dart\$",
-                             rebase_path("../../pkg/analyzer")],
+analyzer_files = exec_script("../../tools/list_dart_files.py",
+                             [rebase_path("../../pkg/analyzer")],
                              "list lines")
 
 application_snapshot("generate_dartanalyzer_snapshot") {
   main_dart = "../../pkg/analyzer_cli/bin/analyzer.dart"
   name = "dartanalyzer"
-  cli_files = exec_script("../../tools/list_files.py",
-                          ["\\.dart\$",
-                           rebase_path("../../pkg/analyzer_cli")],
+  cli_files = exec_script("../../tools/list_dart_files.py",
+                          [rebase_path("../../pkg/analyzer_cli")],
                           "list lines")
   inputs = cli_files + analyzer_files
 }
 
-sdk_lib_files = exec_script("../../tools/list_files.py",
-                            ["\\.dart\$",
-                             rebase_path("../../sdk/lib")],
+sdk_lib_files = exec_script("../../tools/list_dart_files.py",
+                            [rebase_path("../../sdk/lib")],
                             "list lines")
 
 template("generate_summary") {
   assert(defined(invoker.type), "Must specify the summary type")
   type = invoker.type
   assert((type == "spec") || (type == "strong"))
   invoke_dart(target_name) {
     inputs = sdk_lib_files + analyzer_files
 
     output = "$root_gen_dir/$type.sum"
@@ skipping 16 matching lines @@
   }
 }
 
 generate_summary("generate_summary_spec") {
   type = "spec"
 }
 
 generate_summary("generate_summary_strong") {
   type = "strong"
 }