Avoiding double resize of maximized windows upon user switch due to showing and hiding of the shelf

chrome/browser/ui/ash/launcher/chrome_launcher_controller.cc

 // Copyright 2013 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 "chrome/browser/ui/ash/launcher/chrome_launcher_controller.h"
 
 #include <vector>
 
 #include "ash/ash_switches.h"
 #include "ash/desktop_background/desktop_background_controller.h"
@@ skipping 179 matching lines @@
   if (local_pref->IsRecommended() || !has_per_display_prefs)
     return value;
 
   const base::Value* default_value =
       pref_service->GetDefaultPrefValue(local_path);
   std::string default_string;
   default_value->GetAsString(&default_string);
   return default_string;
 }
 
+// Gets the shelf auto hide behavior from prefs for a root window.
+ash::ShelfAutoHideBehavior GetShelfAutoHideBehaviorFromPrefs(
+    Profile* profile,
+    aura::Window* root_window) {
+  // Don't show the shelf in app mode.
+  if (chrome::IsRunningInAppMode())
+    return ash::SHELF_AUTO_HIDE_ALWAYS_HIDDEN;
+
+  // See comment in |kShelfAlignment| as to why we consider two prefs.
+  const std::string behavior_value(
+      GetPrefForRootWindow(profile->GetPrefs(),
+                           root_window,
+                           prefs::kShelfAutoHideBehaviorLocal,
+                           prefs::kShelfAutoHideBehavior));
+
+  // Note: To maintain sync compatibility with old images of chrome/chromeos
+  // the set of values that may be encountered includes the now-extinct
+  // "Default" as well as "Never" and "Always", "Default" should now
+  // be treated as "Never" (http://crbug.com/146773).
+  if (behavior_value == ash::kShelfAutoHideBehaviorAlways)
+    return ash::SHELF_AUTO_HIDE_BEHAVIOR_ALWAYS;
+  return ash::SHELF_AUTO_HIDE_BEHAVIOR_NEVER;
+}
+
+// Gets the shelf alignment from prefs for a root window.
+ash::ShelfAlignment GetShelfAlignmentFromPrefs(Profile* profile,
+                                               aura::Window* root_window) {
+  // See comment in |kShelfAlignment| as to why we consider two prefs.
+  const std::string alignment_value(
+      GetPrefForRootWindow(profile->GetPrefs(),
+                           root_window,
+                           prefs::kShelfAlignmentLocal,
+                           prefs::kShelfAlignment));
+  if (alignment_value == ash::kShelfAlignmentLeft)
+    return ash::SHELF_ALIGNMENT_LEFT;
+  else if (alignment_value == ash::kShelfAlignmentRight)
+    return ash::SHELF_ALIGNMENT_RIGHT;
+  else if (alignment_value == ash::kShelfAlignmentTop)
+    return ash::SHELF_ALIGNMENT_TOP;
+  return ash::SHELF_ALIGNMENT_BOTTOM;
+}
+
 // If prefs have synced and no user-set value exists at |local_path|, the value
 // from |synced_path| is copied to |local_path|.
 void MaybePropagatePrefToLocal(PrefServiceSyncable* pref_service,
                                const char* local_path,
                                const char* synced_path) {
   if (!pref_service->FindPreference(local_path)->HasUserSetting() &&
       pref_service->IsSyncing()) {
     // First time the user is using this machine, propagate from remote to
     // local.
     pref_service->SetString(local_path, pref_service->GetString(synced_path));
@@ skipping 703 matching lines @@
 ash::ShelfModel* ChromeLauncherController::model() {
   return model_;
 }
 
 Profile* ChromeLauncherController::profile() {
   return profile_;
 }
 
 ash::ShelfAutoHideBehavior ChromeLauncherController::GetShelfAutoHideBehavior(
     aura::Window* root_window) const {
-  // Don't show the shelf in app mode.
-  if (chrome::IsRunningInAppMode())
-    return ash::SHELF_AUTO_HIDE_ALWAYS_HIDDEN;
-
-  // See comment in |kShelfAlignment| as to why we consider two prefs.
-  const std::string behavior_value(
-      GetPrefForRootWindow(profile_->GetPrefs(),
-                           root_window,
-                           prefs::kShelfAutoHideBehaviorLocal,
-                           prefs::kShelfAutoHideBehavior));
-
-  // Note: To maintain sync compatibility with old images of chrome/chromeos
-  // the set of values that may be encountered includes the now-extinct
-  // "Default" as well as "Never" and "Always", "Default" should now
-  // be treated as "Never" (http://crbug.com/146773).
-  if (behavior_value == ash::kShelfAutoHideBehaviorAlways)
-    return ash::SHELF_AUTO_HIDE_BEHAVIOR_ALWAYS;
-  return ash::SHELF_AUTO_HIDE_BEHAVIOR_NEVER;
+  return GetShelfAutoHideBehaviorFromPrefs(profile_, root_window);
 }
 
 bool ChromeLauncherController::CanUserModifyShelfAutoHideBehavior(
     aura::Window* root_window) const {
   return profile_->GetPrefs()->
       FindPreference(prefs::kShelfAutoHideBehaviorLocal)->IsUserModifiable();
 }
 
 void ChromeLauncherController::ToggleShelfAutoHideBehavior(
     aura::Window* root_window) {
@@ skipping 480 matching lines @@
 
 bool ChromeLauncherController::IsBrowserFromActiveUser(Browser* browser) {
   // If running multi user mode with separate desktops, we have to check if the
   // browser is from the active user.
   if (chrome::MultiUserWindowManager::GetMultiProfileMode() !=
           chrome::MultiUserWindowManager::MULTI_PROFILE_MODE_SEPARATED)
     return true;
   return multi_user_util::IsProfileFromActiveUser(browser->profile());
 }
 
+bool ChromeLauncherController::ShelfVisibilityChangesProbablyWithUser(
+    aura::Window* root_window,
+    const std::string& user_id) const {
+  Profile* other_profile = multi_user_util::GetProfileFromUserID(user_id);
+  DCHECK_NE(other_profile, profile_);
+
+  // Note: The Auto hide state from preferences is not the same as the actual
+  // visibility of the shelf. Depending on all the various states (full screen,
+  // no window on desktop, multi user, ..) the shelf could be shown - or not.
+  bool currently_shown = ash::SHELF_AUTO_HIDE_BEHAVIOR_NEVER ==
+      GetShelfAutoHideBehaviorFromPrefs(profile_, root_window);
+  bool other_shown = ash::SHELF_AUTO_HIDE_BEHAVIOR_NEVER ==
+      GetShelfAutoHideBehaviorFromPrefs(other_profile, root_window);
+
+  return currently_shown != other_shown ||
+         GetShelfAlignmentFromPrefs(profile_, root_window) !=
+             GetShelfAlignmentFromPrefs(other_profile, root_window);
+}
+
 void ChromeLauncherController::LauncherItemClosed(ash::ShelfID id) {
   IDToItemControllerMap::iterator iter = id_to_item_controller_map_.find(id);
   CHECK(iter != id_to_item_controller_map_.end());
   CHECK(iter->second);
   app_icon_loader_->ClearImage(iter->second->app_id());
   id_to_item_controller_map_.erase(iter);
   int index = model_->ItemIndexByID(id);
   // A "browser proxy" is not known to the model and this removal does
   // therefore not need to be propagated to the model.
   if (index != -1)
@@ skipping 238 matching lines @@
 }
 
 void ChromeLauncherController::SetShelfAlignmentFromPrefs() {
   if (!ash::ShelfWidget::ShelfAlignmentAllowed())
     return;
 
   aura::Window::Windows root_windows = ash::Shell::GetAllRootWindows();
 
   for (aura::Window::Windows::const_iterator iter = root_windows.begin();
        iter != root_windows.end(); ++iter) {
-    // See comment in |kShelfAlignment| as to why we consider two prefs.
-    const std::string alignment_value(
-        GetPrefForRootWindow(profile_->GetPrefs(),
-                             *iter,
-                             prefs::kShelfAlignmentLocal,
-                             prefs::kShelfAlignment));
-    ash::ShelfAlignment alignment = ash::SHELF_ALIGNMENT_BOTTOM;
-    if (alignment_value == ash::kShelfAlignmentLeft)
-      alignment = ash::SHELF_ALIGNMENT_LEFT;
-    else if (alignment_value == ash::kShelfAlignmentRight)
-      alignment = ash::SHELF_ALIGNMENT_RIGHT;
-    else if (alignment_value == ash::kShelfAlignmentTop)
-      alignment = ash::SHELF_ALIGNMENT_TOP;
-    ash::Shell::GetInstance()->SetShelfAlignment(alignment, *iter);
+    ash::Shell::GetInstance()->SetShelfAlignment(
+        GetShelfAlignmentFromPrefs(profile_, *iter), *iter);
   }
 }
 
 void ChromeLauncherController::SetShelfBehaviorsFromPrefs() {
   SetShelfAutoHideBehaviorFromPrefs();
   SetShelfAlignmentFromPrefs();
 }
 
 #if defined(OS_CHROMEOS)
 void ChromeLauncherController::SetVirtualKeyboardBehaviorFromPrefs() {
@@ skipping 339 matching lines @@
 }
 
 void ChromeLauncherController::ReleaseProfile() {
   if (app_sync_ui_state_)
     app_sync_ui_state_->RemoveObserver(this);
 
   PrefServiceSyncable::FromProfile(profile_)->RemoveObserver(this);
 
   pref_change_registrar_.RemoveAll();
 }