Remove the deprecated Alt+Shift shortcut completely

ash/common/accelerators/accelerator_controller.cc

 // Copyright (c) 2012 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.
 
 #include "ash/common/accelerators/accelerator_controller.h"
 
 #include <utility>
 
 #include "ash/common/accelerators/accelerator_commands.h"
 #include "ash/common/accelerators/accelerator_controller_delegate.h"
@@ skipping 155 matching lines @@
   // Touchscreen users have better window switching options. It would be
   // preferable if we could tell whether this event actually came from a virtual
   // keyboard, but there's no easy way to do so, thus we block Alt+Tab when the
   // virtual keyboard is showing, even if it came from a real keyboard. See
   // http://crbug.com/638269
   keyboard::KeyboardController* keyboard_controller =
       keyboard::KeyboardController::GetInstance();
   return !(keyboard_controller && keyboard_controller->keyboard_visible());
 }
 
-// We must avoid showing the Deprecated NEXT_IME notification erronously.
-bool ShouldShowDeprecatedNextImeNotification(
-    const ui::Accelerator& previous_accelerator) {
-  // We only show the deprecation notification if the previous accelerator key
-  // is ONLY either Shift, or Alt.
-  const ui::KeyboardCode previous_key_code = previous_accelerator.key_code();
-  switch (previous_key_code) {
-    case ui::VKEY_SHIFT:
-    case ui::VKEY_LSHIFT:
-    case ui::VKEY_RSHIFT:
-    case ui::VKEY_MENU:
-    case ui::VKEY_LMENU:
-    case ui::VKEY_RMENU:
-      return true;
-
-    default:
-      return false;
-  }
-}
-
 void HandleNextIme(ImeControlDelegate* ime_control_delegate) {
   base::RecordAction(UserMetricsAction("Accel_Next_Ime"));
   ime_control_delegate->HandleNextIme();
 }
 
 void HandleOpenFeedbackPage() {
   base::RecordAction(UserMetricsAction("Accel_Open_Feedback_Page"));
   WmShell::Get()->new_window_controller()->OpenFeedbackPage();
 }
 
@@ skipping 435 matching lines @@
     auto itr = actions_with_deprecations_.find(action);
     if (itr != actions_with_deprecations_.end()) {
       const DeprecatedAcceleratorData* data = itr->second;
       if (deprecated_accelerators_.count(accelerator)) {
         // This accelerator has been deprecated and should be treated according
         // to its |DeprecatedAcceleratorData|.
 
         // Record UMA stats.
         RecordUmaHistogram(data->uma_histogram_name, DEPRECATED_USED);
 
-        // We always display the notification as long as this entry exists,
-        // except for NEXT_IME, we must check to avoid showing it for the wrong
-        // shortcut, as Alt+Shift is tricky and trigger the action on release.
-        if (delegate_ &&
-            (action != NEXT_IME ||
-             (action == NEXT_IME &&
-              ShouldShowDeprecatedNextImeNotification(
-                  accelerator_history_->previous_accelerator())))) {
+        if (delegate_) {

[James Cook, 2017/01/26 22:24:52]

It's not your fault, but this function is deeply nested and hard to read. Can
you try to make it less nest-y, either by pulling out the deprecated accelerator
handling into a separate function or inverting some conditionals?

[afakhry, 2017/01/27 03:35:06]

Actually, it is my fault, I'm the one who wrote this in the first place. :D I
should have known better. Thanks for suggesting the clean up.

Please take a look at the refactored code.

+          // We always display the notification as long as this entry exists.
           delegate_->ShowDeprecatedAcceleratorNotification(
               data->uma_histogram_name, data->notification_message_id,
               data->old_shortcut_id, data->new_shortcut_id);
         }
 
         if (!data->deprecated_enabled)
           return false;
       } else {
         // This is a new accelerator replacing the old deprecated one.
         // Record UMA stats and proceed normally.
@@ skipping 498 matching lines @@
   if (wm_shell->mru_window_tracker()->BuildMruWindowList().empty() &&
       actions_needing_window_.find(action) != actions_needing_window_.end()) {
     wm_shell->accessibility_delegate()->TriggerAccessibilityAlert(
         A11Y_ALERT_WINDOW_NEEDED);
     return RESTRICTION_PREVENT_PROCESSING_AND_PROPAGATION;
   }
   return RESTRICTION_NONE;
 }
 
 }  // namespace ash