SELECT element: Ignore synthetic events.

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 c1b513711c3747b6df2204199d5be67d57f4eaf1..8b99e8bd7a683bb1bf2e89d3ef6e32b832734749 100644
--- a/third_party/WebKit/Source/core/html/HTMLSelectElement.cpp
+++ b/third_party/WebKit/Source/core/html/HTMLSelectElement.cpp
@@ -1306,6 +1306,10 @@ bool HTMLSelectElement::shouldOpenPopupForKeyPressEvent(KeyboardEvent *event)
 
 void HTMLSelectElement::menuListDefaultEventHandler(Event* event)
 {
+    // TODO(tkent): Remove isTrusted check when we ship
+    // TrustedEventsDefaultAction.
+    if (!event->isTrusted())
+        return;
     if (event->type() == EventTypeNames::keydown) {
         if (!layoutObject() || !event->isKeyboardEvent())
             return;