[iOS] Remove dependencies on //ipc from //ui/events.

Remove problematic dependencies on //ipc from //ui/events when targetting
iOS (Chrome on iOS cannot depends on //ipc nor //content).

BUG=459705

Review URL: https://codereview.chromium.org/1802333002

Cr-Commit-Position: refs/heads/master@{#381631}

ui/events/BUILD.gn

@@ -61,7 +61,6 @@ component("events_base") {
   deps = [
     ":dom_keycode_converter",
     "//base/third_party/dynamic_annotations",
-    "//ipc:param_traits",
     "//skia",
   ]
 
@@ -95,6 +94,10 @@ component("events_base") {
       "keycodes/xkb_keysym.h",
     ]
   }
+
+  if (!is_ios) {
+    deps += [ "//ipc:param_traits" ]
+  }
 }
 
 component("events") {
@@ -358,7 +361,6 @@ test("events_unittests") {
     "gesture_detection/touch_disposition_gesture_filter_unittest.cc",
     "gesture_detection/velocity_tracker_unittest.cc",
     "gestures/fling_curve_unittest.cc",
-    "ipc/latency_info_param_traits_unittest.cc",
     "keycodes/dom/keycode_converter_unittest.cc",
     "keycodes/keyboard_code_conversion_unittest.cc",
     "keycodes/platform_key_map_win_unittest.cc",
@@ -377,12 +379,10 @@ test("events_unittests") {
     "//base",
     "//base/test:run_all_unittests",
     "//base/test:test_support",
-    "//ipc:test_support",
     "//skia",
     "//testing/gmock",
     "//testing/gtest",
     "//ui/events/devices",
-    "//ui/events/ipc:events_ipc",
     "//ui/events/platform",
     "//ui/gfx:test_support",
   ]
@@ -392,12 +392,15 @@ test("events_unittests") {
       "blink/input_handler_proxy_unittest.cc",
       "blink/input_scroll_elasticity_controller_unittest.cc",
       "gestures/blink/web_gesture_curve_impl_unittest.cc",
+      "ipc/latency_info_param_traits_unittest.cc",
     ]
     deps += [
       "//cc",
+      "//ipc:test_support",
       "//third_party/WebKit/public:blink_headers",
       "//ui/events/blink",
       "//ui/events/gestures/blink",
+      "//ui/events/ipc:events_ipc",
     ]
   }
 

ui/events/latency_info.h

@@ -15,9 +15,12 @@
 #include "base/memory/scoped_ptr.h"
 #include "base/time/time.h"
 #include "base/trace_event/trace_event.h"
-#include "ipc/ipc_param_traits.h"
 #include "ui/events/events_base_export.h"
 
+#if !defined(OS_IOS)
+#include "ipc/ipc_param_traits.h"  // nogncheck
+#endif
+
 namespace ui {
 
 // When adding new components, or new metrics based on LatencyInfo,
@@ -229,7 +232,9 @@ class EVENTS_BASE_EXPORT LatencyInfo {
   // Whether a terminal component has been added.
   bool terminated_;
 
+#if !defined(OS_IOS)
   friend struct IPC::ParamTraits<ui::LatencyInfo>;
+#endif
 };
 
 }  // namespace ui