Fix running gn gen for //ui/* targets on iOS.

ui/events/BUILD.gn

 # Copyright 2014 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")
 
 static_library("dom_keycode_converter") {
   sources = [
     "keycodes/dom/dom_code.h",
@@ skipping 315 matching lines @@
   deps = [
     ":dom_keycode_converter",
     ":events",
     ":events_base",
     ":gesture_detection",
     ":test_support",
     "//base",
     "//base/test:run_all_unittests",
     "//skia",
     "//testing/gtest",
-    "//third_party/WebKit/public:blink_headers",
     "//ui/events/devices",
-    "//ui/events/gestures/blink",
     "//ui/events/platform",
     "//ui/gfx:test_support",
   ]
 
+  if (!is_ios) {
+    deps += [
+      "//third_party/WebKit/public:blink_headers",
+      "//ui/events/gestures/blink",
+    ]
+  }
+
   include_dirs = [ "//testing/gmock/include" ]
 
   if (use_x11) {
     configs += [ "//build/config/linux:x11" ]
     deps += [ "//ui/gfx/x" ]
   } else {
     sources -= [
       "devices/x11/device_data_manager_x11_unittest.cc",
       "x/events_x_unittest.cc",
     ]
@@ skipping 27 matching lines @@
 if (is_nacl) {
   source_set("latency_info") {
     sources = [
       "ipc/latency_info_param_traits.cc",
       "ipc/latency_info_param_traits.h",
       "latency_info.cc",
       "latency_info.h",
     ]
   }
 }