[InputEvent] Support |sequence<Range> getRanges()| in 'beforeinput'

third_party/WebKit/Source/core/events/InputEvent.h

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef InputEvent_h
 #define InputEvent_h
 
 #include "core/events/InputEventInit.h"
 #include "core/events/UIEvent.h"
 
 namespace blink {
 
+class Range;
+
 class InputEvent final : public UIEvent {
     DEFINE_WRAPPERTYPEINFO();
 
 public:
     static InputEvent* create()
     {
         return new InputEvent;
     }
 
     static InputEvent* create(const AtomicString& type, const InputEventInit& initializer)
@@ skipping 17 matching lines @@
     enum EventCancelable : bool {
         NotCancelable = false,
         IsCancelable = true,
     };
 
     enum EventIsComposing : bool {
         NotComposing = false,
         IsComposing = true,
     };
 
-    static InputEvent* createBeforeInput(InputType, const String& data, EventCancelable, EventIsComposing);
+    static InputEvent* createBeforeInput(InputType, const String& data, EventCancelable, EventIsComposing, const RangeVector*);
 
     String inputType() const;
     const String& data() const { return m_data; }
     bool isComposing() const { return m_isComposing; }
+    // Returns a copy of target ranges during event dispatch, and returns an empty
+    // vector after dispatch.
+    // TODO(chongz): Return Vector<StaticRange>.
+    HeapVector<Member<Range>> getRanges() const { return m_ranges; };
 
     bool isInputEvent() const override;
 
+    EventDispatchMediator* createMediator() override;
+
     DECLARE_VIRTUAL_TRACE();
 
 private:
+    friend class InputEventDispatchMediator;
     InputEvent();
     InputEvent(const AtomicString&, const InputEventInit&);
 
     InputType m_inputType;
     String m_data;
     bool m_isComposing;
+    // |m_ranges| is the target ranges for the event and will be live during
+    // event dispatch, but will get cleared after dispatch to save resources.
+    RangeVector m_ranges;
+};
+
+class InputEventDispatchMediator final : public EventDispatchMediator {
+public:
+    static InputEventDispatchMediator* create(InputEvent*);
+
+private:
+    explicit InputEventDispatchMediator(InputEvent*);
+    InputEvent& event() const;
+    DispatchEventResult dispatchEvent(EventDispatcher&) const override;
 };
 
 DEFINE_EVENT_TYPE_CASTS(InputEvent);
 
 } // namespace blink
 
 #endif // InputEvent_h