IME for Mus: Avoid crash in InitWindowCandidateView().

chrome/browser/chromeos/input_method/candidate_window_controller_impl.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 "chrome/browser/chromeos/input_method/candidate_window_controller_impl.h"
 
 #include <string>
 #include <vector>
 
 #include "ash/public/cpp/shell_window_ids.h"
 #include "ash/shell.h"
 #include "ash/wm/window_util.h"
 #include "base/logging.h"
 #include "chrome/browser/chromeos/input_method/mode_indicator_controller.h"
+#include "chrome/browser/ui/ash/ash_util.h"
 #include "ui/base/ime/ime_bridge.h"
 #include "ui/chromeos/ime/infolist_window.h"
 #include "ui/views/widget/widget.h"
 
 namespace chromeos {
 namespace input_method {
 
 namespace {
 
 }  // namespace
@@ skipping 12 matching lines @@
   if (candidate_window_view_) {
     candidate_window_view_->RemoveObserver(this);
     candidate_window_view_->GetWidget()->RemoveObserver(this);
   }
 }
 
 void CandidateWindowControllerImpl::InitCandidateWindowView() {
   if (candidate_window_view_)
     return;
 
-  aura::Window* active_window = ash::wm::GetActiveWindow();
-  candidate_window_view_ =
-      new ui::ime::CandidateWindowView(ash::Shell::GetContainer(
-          active_window ? active_window->GetRootWindow()
-                        : ash::Shell::GetTargetRootWindow(),
-          ash::kShellWindowId_SettingBubbleContainer));
+  gfx::NativeView parent = nullptr;
+  if (!chrome::IsRunningInMash()) {
+    aura::Window* active_window = ash::wm::GetActiveWindow();
+    parent = ash::Shell::GetContainer(
+        active_window ? active_window->GetRootWindow()
+                      : ash::Shell::GetTargetRootWindow(),
+        ash::kShellWindowId_SettingBubbleContainer);
+  }
+  candidate_window_view_ = new ui::ime::CandidateWindowView(parent);

[sadrul, 2017/01/23 18:20:11]

Can you comment on how this candidate window will be parented in mash?

[Hadi, 2017/01/23 21:11:34]

Setting parent as null doesn't provide the same behavior as in ChromeOS. For
example, when dragging the window in ChromeOS the popup is also moved, but in
mus+ash the popup disappears.

This change avoids crashing and works for most cases until we find a better
solution. Non-latin text input is not high priority for near future, so I think
we can postpone for later.

I changed the title and description of this CL and added a TODO comment.

   candidate_window_view_->AddObserver(this);
   candidate_window_view_->SetCursorBounds(cursor_bounds_, composition_head_);
   views::Widget* widget = candidate_window_view_->InitWidget();
   widget->AddObserver(this);
   widget->Show();
   for (auto& observer : observers_)
     observer.CandidateWindowOpened();
 }
 
 void CandidateWindowControllerImpl::Hide() {
@@ skipping 128 matching lines @@
   observers_.AddObserver(observer);
 }
 
 void CandidateWindowControllerImpl::RemoveObserver(
     CandidateWindowController::Observer* observer) {
   observers_.RemoveObserver(observer);
 }
 
 }  // namespace input_method
 }  // namespace chromeos