VR: Disable select element in VR mode via WebPreferences

third_party/WebKit/Source/core/html/HTMLSelectElement.cpp

Index: third_party/WebKit/Source/core/html/HTMLSelectElement.cpp
diff --git a/third_party/WebKit/Source/core/html/HTMLSelectElement.cpp b/third_party/WebKit/Source/core/html/HTMLSelectElement.cpp
index 9830da4f64792410d883ba2eec74fb7ea779f764..cc47e407a1b57635e3b0d07aa37ae655078c979e 100644
--- a/third_party/WebKit/Source/core/html/HTMLSelectElement.cpp
+++ b/third_party/WebKit/Source/core/html/HTMLSelectElement.cpp
@@ -1949,6 +1949,9 @@ void HTMLSelectElement::ShowPopup() {
   if (!popup_)
     popup_ = GetDocument().GetPage()->GetChromeClient().OpenPopupMenu(
         *GetDocument().GetFrame(), *this);
+  if (!popup_)
+    return;
+
   popup_is_visible_ = true;
   ObserveTreeMutation();