<select>: ignore modified keydown events in some cases

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 9cb94478f0dbf20b4a3373cde5fa07bc6e09c7b4..ba5a8848427ccbfe1b80301a07c28367f6e47dcc 100644
--- a/third_party/WebKit/Source/core/html/HTMLSelectElement.cpp
+++ b/third_party/WebKit/Source/core/html/HTMLSelectElement.cpp
@@ -1287,6 +1287,11 @@ void HTMLSelectElement::menuListDefaultEventHandler(Event* event) {
         !isSpatialNavigationEnabled(document().frame()))
       return;
 
+    int ignoreModifiers = PlatformEvent::ShiftKey | PlatformEvent::CtrlKey |
+                          PlatformEvent::AltKey | PlatformMouseEvent::MetaKey;
+    if (keyEvent->modifiers() & ignoreModifiers)
+      return;
+
     const String& key = keyEvent->key();
     bool handled = true;
     const ListItems& listItems = this->listItems();