Implement MouseEvent.getModifierState

Source/core/events/UIEventWithKeyState.cpp

 /*
  * Copyright (C) 2006 Apple Computer, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 17 matching lines @@
 void UIEventWithKeyState::didCreateEventInIsolatedWorld(bool ctrlKey, bool shiftKey, bool altKey, bool metaKey)
 {
 #if OS(MACOSX)
     const bool newTabModifierSet = metaKey;
 #else
     const bool newTabModifierSet = ctrlKey;
 #endif
     s_newTabModifierSetFromIsolatedWorld |= newTabModifierSet;
 }
 
+bool UIEventWithKeyState::getModifierState(const String& keyIdentifier) const
+{
+    // FIXME: The following keyIdentifiers are not supported yet (crbug.com/265458):
+    // "AltGraph", "CapsLock", "Fn", "NumLock", "ScrollLock", "SymbolLock", "OS".
+    if (keyIdentifier == "Control")
+        return ctrlKey();
+    if (keyIdentifier == "Shift")
+        return shiftKey();
+    if (keyIdentifier == "Alt")
+        return altKey();
+    if (keyIdentifier == "Meta")
+        return metaKey();
+    return false;
+}
+
 UIEventWithKeyState* findEventWithKeyState(Event* event)
 {
     for (Event* e = event; e; e = e->underlyingEvent())
         if (e->isKeyboardEvent() || e->isMouseEvent())
             return static_cast<UIEventWithKeyState*>(e);
     return nullptr;
 }
 
 } // namespace blink