A tricky fix for Issue 1845 (Take 2)....

chrome/browser/renderer_host/render_widget_host.h

 // Copyright (c) 2006-2008 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 CHROME_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_H_
 #define CHROME_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_H_
 
 #include <queue>
 #include <vector>
 
 #include "base/gfx/size.h"
 #include "base/scoped_ptr.h"
 #include "base/timer.h"
 #include "chrome/common/ipc_channel.h"
 #include "chrome/common/native_web_keyboard_event.h"
 #include "testing/gtest/include/gtest/gtest_prod.h"
 #include "webkit/glue/webinputevent.h"
+#include "webkit/glue/webtextdirection.h"
 
 namespace gfx {
 class Rect;
 }
 
 class BackingStore;
 class PaintObserver;
 class RenderProcessHost;
 class RenderWidgetHostView;
 class TransportDIB;
@@ skipping 176 matching lines @@
   // theme handles are invalid and the renderer must obtain new ones and
   // repaint.
   void SystemThemeChanged();
 
   // Forwards the given message to the renderer. These are called by the view
   // when it has received a message.
   void ForwardMouseEvent(const WebMouseEvent& mouse_event);
   void ForwardWheelEvent(const WebMouseWheelEvent& wheel_event);
   void ForwardKeyboardEvent(const NativeWebKeyboardEvent& key_event);
 
+  // Update the text direction of the focused input element and notify it to a
+  // renderer process.
+  // These functions have two usage scenarios: changing the text direction
+  // from a menu (as Safari does), and; changing the text direction when a user
+  // presses a set of keys (as IE and Firefox do).
+  // 1. Change the text direction from a menu.
+  // In this scenario, we receive a menu event only once and we should update
+  // the text direction immediately when a user chooses a menu item. So, we
+  // should call both functions at once as listed in the following snippet.
+  //   void RenderViewHost::SetTextDirection(WebTextDirection direction) {
+  //     UpdateTextDirection(direction);
+  //     NotifyTextDirection();
+  //   }
+  // 2. Change the text direction when pressing a set of keys.
+  // Becauses of auto-repeat, we may receive the same key-press event many
+  // times while we presses the keys and it is nonsense to send the same IPC
+  // messsage every time when we receive a key-press event.
+  // To suppress the number of IPC messages, we just update the text direction
+  // when receiving a key-press event and send an IPC message when we release
+  // the keys as listed in the following snippet.
+  //   if (key_event.type == WebKeyboardEvent::KEY_DOWN) {
+  //     if (key_event.windows_key_code == 'A' &&
+  //         key_event.modifiers == WebKeyboardEvent::CTRL_KEY) {
+  //       UpdateTextDirection(dir);
+  //     }
+  //   } else if (key_event.type == WebKeyboardEvent::KEY_UP) {
+  //     NotifyTextDirection();
+  //   }
+  // Note: we cannot undo this change for compatibility with Firefox and IE.
+  void UpdateTextDirection(WebTextDirection direction);
+  void NotifyTextDirection();
+
   // This is for derived classes to give us access to the resizer rect.
   // And to also expose it to the RenderWidgetHostView.
   virtual gfx::Rect GetRootWindowResizerRect() const;
 
  protected:
   // Internal implementation of the public Forward*Event() methods.
   void ForwardInputEvent(const WebInputEvent& input_event, int event_size);
 
   // Called when we receive a notification indicating that the renderer
   // process has gone. This will reset our state so that our state will be
@@ skipping 132 matching lines @@
   base::TimeTicks repaint_start_time_;
 
   // Queue of keyboard events that we need to track.
   typedef std::queue<NativeWebKeyboardEvent> KeyQueue;
 
   // A queue of keyboard events. We can't trust data from the renderer so we
   // stuff key events into a queue and pop them out on ACK, feeding our copy
   // back to whatever unhandled handler instead of the returned version.
   KeyQueue key_queue_;
 
+  // Set when we update the text direction of the selected input element.
+  bool text_direction_updated_;
+  WebTextDirection text_direction_;
+
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHost);
 };
 
 #endif  // CHROME_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_H_