Add key based scrolling on magnified screen for kiosk mode.

chrome/browser/ui/ash/event_rewriter.h

Index: chrome/browser/ui/ash/event_rewriter.h
diff --git a/chrome/browser/ui/ash/event_rewriter.h b/chrome/browser/ui/ash/event_rewriter.h
index f08507582a83135d4e6027e22b6762f449777bf4..0747bdce2719b491954efef67fe0acfec57155e7 100644
--- a/chrome/browser/ui/ash/event_rewriter.h
+++ b/chrome/browser/ui/ash/event_rewriter.h
@@ -31,6 +31,7 @@ class RootWindow;
 namespace chromeos {
 
 class KeyboardDrivenEventRewriter;
+class AccessibilityEventRewriter;
 
 namespace input_method {
 class XKeyboard;
@@ -158,7 +159,7 @@ class EventRewriter : public ash::EventRewriterDelegate,
   const PrefService* GetPrefService() const;
 
   // Rewrites the |event| by applying all RewriteXXX functions as needed.
-  void Rewrite(ui::KeyEvent* event);
+  ash::EventRewriterDelegate::Action Rewrite(ui::KeyEvent* event);
 
   // Rewrites a modifier key press/release following the current user
   // preferences.
@@ -197,12 +198,12 @@ class EventRewriter : public ash::EventRewriterDelegate,
   // Rewrites the located |event|.
   void RewriteLocatedEvent(ui::LocatedEvent* event);
 
-  // Overwrites |event| with the keycodes and flags.
-  void OverwriteEvent(ui::KeyEvent* event,
-                      unsigned int new_native_keycode,
-                      unsigned int new_native_state,
-                      ui::KeyboardCode new_keycode,
-                      int new_flags);
+  //  Rewrites the event for accessibility.
+  //  * Press and Hold [Shift+{Up/Down/Left/Right} -> Shift+NUMPAD{6789}
+  //  * Release[Shift+{Up/Down/Left/Right}] -> Shift+{Up/Down/Left/Right}
+  bool RewriteAccessibilityKeys(
+      ui::KeyEvent* event,
+      ash::EventRewriterDelegate::Action* action);
 
   // Checks the type of the |device_name|, and inserts a new entry to
   // |device_id_to_type_|.
@@ -218,10 +219,20 @@ class EventRewriter : public ash::EventRewriterDelegate,
                                 int* remapped_flags,
                                 unsigned int* remapped_native_modifiers) const;
 
+  // Overwrites |event| with the keycodes and flags.
+  static void OverwriteEvent(ui::KeyEvent* event,
+                             unsigned int new_native_keycode,
+                             unsigned int new_native_state,
+                             ui::KeyboardCode new_keycode,
+                             int new_flags);
+
   std::map<int, DeviceType> device_id_to_type_;
   int last_device_id_;
 
 #if defined(OS_CHROMEOS)
+  class AccessibilityEventRewriter;
+  friend class AccessibilityEventRewriter;
+
   // A mapping from X11 KeySym keys to KeyCode values.
   base::hash_map<unsigned long, unsigned long> keysym_to_keycode_map_;
 
@@ -232,6 +243,9 @@ class EventRewriter : public ash::EventRewriterDelegate,
 
   scoped_ptr<chromeos::KeyboardDrivenEventRewriter>
       keyboard_driven_event_rewriter_;
+
+  scoped_ptr<AccessibilityEventRewriter>
+      accessibility_event_rewriter_;
 #endif
 
   const PrefService* pref_service_for_testing_;