gtk2_ui.h should be included only for X11

This patch fixes a build break in ozone-wayland.

BUG=None

Review URL: https://codereview.chromium.org/1015323002

Cr-Commit-Position: refs/heads/master@{#321441}

chrome/browser/ui/aura/chrome_browser_main_extra_parts_aura.cc

@@ -19,10 +19,9 @@
 #include "ui/gfx/screen.h"
 #include "ui/views/widget/native_widget_aura.h"
 
-#if defined(USE_X11) && !defined(OS_CHROMEOS)
+#if defined(OS_LINUX) && !defined(OS_CHROMEOS)
 #include "base/prefs/pref_service.h"
 #include "chrome/browser/profiles/profile.h"
-#include "chrome/browser/ui/libgtk2ui/gtk2_ui.h"
 #include "chrome/common/pref_names.h"
 #include "ui/aura/window.h"
 #include "ui/base/ime/input_method_initializer.h"
@@ -30,6 +29,10 @@
 #include "ui/views/linux_ui/linux_ui.h"
 #endif
 
+#if defined(USE_X11) && !defined(OS_CHROMEOS)
+#include "chrome/browser/ui/libgtk2ui/gtk2_ui.h"
+#endif
+
 #if defined(USE_ASH)
 #include "chrome/browser/ui/ash/ash_util.h"
 #endif  // defined(USE_ASH)