Stop building FilePathWatcher on iOS.

base/BUILD.gn

 # Copyright (c) 2013 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import("//build/config/ui.gni")
 import("//testing/test.gni")
 
 if (is_android) {
   import("//build/config/android/rules.gni")
 }
@@ skipping 626 matching lines @@
     "win/win_util.cc",
     "win/win_util.h",
     "win/windows_version.cc",
     "win/windows_version.h",
     "win/wrapped_window_proc.cc",
     "win/wrapped_window_proc.h",
   ]
 
   if (is_ios) {
     sources -= [
+      "files/file_path_watcher.cc",
+      "files/file_path_watcher.h",
+      "files/file_path_watcher_fsevents.cc",
+      "files/file_path_watcher_fsevents.h",
+      "files/file_path_watcher_kqueue.cc",
+      "files/file_path_watcher_kqueue.h",
       "message_loop/message_pump_libevent.cc",
       "message_loop/message_pump_libevent.h",
     ]
-
-    set_sources_assignment_filter([])
-    sources += [ "files/file_path_watcher_mac.cc" ]
-    set_sources_assignment_filter(sources_assignment_filter)
   }
 
   sources -= [
     "sys_info_freebsd.cc",
     "sys_info_openbsd.cc",
   ]
 
   data = []
 
   configs += [
@@ skipping 813 matching lines @@
       ":base_java_unittest_support",
     ]
 
     # TODO(brettw) I think this should not be here, we should not be using
     # isolate files.
     isolate_file = "base_unittests.isolate"
   }
 
   if (is_ios) {
     sources -= [
+      "files/file_path_watcher_unittest.cc",
       "memory/discardable_shared_memory_unittest.cc",
       "memory/shared_memory_unittest.cc",
       "process/memory_unittest.cc",
       "process/process_unittest.cc",
       "process/process_util_unittest.cc",
     ]
 
     # Pull in specific Mac files for iOS (which have been filtered out by file
     # name rules).
     set_sources_assignment_filter([])
@@ skipping 194 matching lines @@
 
   # GYP: //base.gyp:base_java_unittest_support
   android_library("base_java_unittest_support") {
     deps = [
       ":base_java",
     ]
     java_files =
         [ "test/android/java/src/org/chromium/base/ContentUriTestUtils.java" ]
   }
 }