Delete the GTK+ port of Chrome.

content/renderer/render_view_impl.cc

Index: content/renderer/render_view_impl.cc
diff --git a/content/renderer/render_view_impl.cc b/content/renderer/render_view_impl.cc
index 45942b1fcfe32edc4972ca6e69782aef75da3206..d923dbb20cdd5b9f9dc4b7ed7de69e4feae5cba0 100644
--- a/content/renderer/render_view_impl.cc
+++ b/content/renderer/render_view_impl.cc
@@ -3365,17 +3365,11 @@ void RenderViewImpl::OnSetRendererPrefs(
   renderer_preferences_ = renderer_prefs;
   UpdateFontRenderingFromRendererPrefs();
 
-#if defined(USE_DEFAULT_RENDER_THEME) || defined(TOOLKIT_GTK)
+#if defined(USE_DEFAULT_RENDER_THEME)
   if (renderer_prefs.use_custom_colors) {
     WebColorName name = blink::WebColorWebkitFocusRingColor;
     blink::setNamedColors(&name, &renderer_prefs.focus_ring_color, 1);
     blink::setCaretBlinkInterval(renderer_prefs.caret_blink_interval);
-#if defined(TOOLKIT_GTK)
-    ui::NativeTheme::instance()->SetScrollbarColors(
-        renderer_prefs.thumb_inactive_color,
-        renderer_prefs.thumb_active_color,
-        renderer_prefs.track_color);
-#endif  // defined(TOOLKIT_GTK)
 
     if (webview()) {
       webview()->setSelectionColors(