cros: Fix restoring session windows after crash inconsistent minimized window counts

chrome/browser/sessions/session_restore.cc

 // Copyright 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/sessions/session_restore.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <list>
@@ skipping 392 matching lines @@
       Browser* browser = nullptr;
       if (!has_tabbed_browser &&
           (*i)->type == sessions::SessionWindow::TYPE_TABBED)
         has_tabbed_browser = true;
       if (i == windows->begin() &&
           (*i)->type == sessions::SessionWindow::TYPE_TABBED && browser_ &&
           browser_->is_type_tabbed() &&
           !browser_->profile()->IsOffTheRecord()) {
         // The first set of tabs is added to the existing browser.
         browser = browser_;
+        // If the first set of tabs belongs to minimized browser, the existing
+        // browser should be minimized to keep consistent show state.
+        if ((*i)->show_state == ui::SHOW_STATE_MINIMIZED)

[sky, 2017/02/23 21:41:06]

If there is only one window, I think we should not minimize it. Otherwise it
looks like nothing opened. Also, I think this should set the initial show state
(assuming browser isn't visible already).

[Qiang(Joe) Xu, 2017/03/06 22:36:03]

Yes, I agree. We shall not minimize here. 
Another way is, for restoring pages to the existing browser, we already have the
activated browser (the existing browser), but the first set of tabs may not have
|active_window_id|, which leads to another |browser_to_activate| below.

After this change, it works well on emulator tests. But it may occasionally
break on device, and I find it is because
https://cs.chromium.org/chromium/src/chrome/browser/sessions/session_restore....
function call will change browser from minimized to unminimized. It doesn't
always change. I believe this is a separate issue.

+          browser->window()->Minimize();
       } else {
 #if defined(OS_CHROMEOS)
         chromeos::BootTimesRecorder::Get()->AddLoginTimeMarker(
             "SessionRestore-CreateRestoredBrowser-Start", false);
 #endif
         // Show the first window if none are visible.
         ui::WindowShowState show_state = (*i)->show_state;
         if (!has_visible_browser) {
           show_state = ui::SHOW_STATE_NORMAL;
           has_visible_browser = true;
@@ skipping 421 matching lines @@
 // static
 SessionRestore::CallbackSubscription
     SessionRestore::RegisterOnSessionRestoredCallback(
         const base::Callback<void(int)>& callback) {
   return on_session_restored_callbacks()->Add(callback);
 }
 
 // static
 base::CallbackList<void(int)>*
     SessionRestore::on_session_restored_callbacks_ = nullptr;