Adds KeyEvent::properties

ui/events/event.h

Index: ui/events/event.h
diff --git a/ui/events/event.h b/ui/events/event.h
index cfac55ca118f57abcff2dd76918676f0eece173a..c65d8d1507951d87d63908e9f968bfdda22bf7d7 100644
--- a/ui/events/event.h
+++ b/ui/events/event.h
@@ -8,6 +8,9 @@
 #include <stdint.h>
 
 #include <memory>
+#include <string>
+#include <unordered_map>
+#include <vector>
 
 #include "base/compiler_specific.h"
 #include "base/event_types.h"
@@ -798,6 +801,8 @@ class EVENTS_EXPORT PointerEvent : public LocatedEvent {
 //
 class EVENTS_EXPORT KeyEvent : public Event {
  public:
+  using Properties = std::unordered_map<std::string, std::vector<uint8_t>>;
+
   // Create a KeyEvent from a NativeEvent. For Windows this native event can
   // be either a keystroke message (WM_KEYUP/WM_KEYDOWN) or a character message
   // (WM_CHAR). Other systems have only keystroke events.
@@ -904,6 +909,14 @@ class EVENTS_EXPORT KeyEvent : public Event {
   // (Native X11 event flags describe the state before the event.)
   void NormalizeFlags();
 
+  // Sets the properties associated with this KeyEvent.
+  void SetProperties(const Properties& properties);
+
+  // Returns the properties associated with this event, which may be null.
+  // The properties are meant to provide a way to associate arbitrary key/value
+  // pairs with KeyEvents and not used by KeyEvent.
+  const Properties* properties() const { return properties_.get(); }
+
  protected:
   friend class KeyEventTestApi;
 
@@ -914,6 +927,8 @@ class EVENTS_EXPORT KeyEvent : public Event {
   // Determine key_ on a keystroke event from code_ and flags().
   void ApplyLayout() const;
 
+  static bool IsRepeated(const KeyEvent& event);
+
   KeyboardCode key_code_;
 
   // DOM KeyboardEvent |code| (e.g. DomCode::US_A, DomCode::SPACE).
@@ -940,7 +955,7 @@ class EVENTS_EXPORT KeyEvent : public Event {
   // it may be set only if and when GetCharacter() or GetDomKey() is called.
   mutable DomKey key_ = DomKey::NONE;
 
-  static bool IsRepeated(const KeyEvent& event);
+  std::unique_ptr<Properties> properties_;

[sadrul, 2017/03/21 17:21:14]

Should this be a base::Optional?

[sky, 2017/03/21 17:25:37]

My understanding is that base::Optional's size is always that of the element,
where as unique_ptr size is that of the pointer value. As most KeyEvents won't
contain properties I went with unique_ptr.

 
   static KeyEvent* last_key_event_;
 };