mojo api for view based lockscreen

ash/login/ui/lock_contents_view.cc

 // Copyright 2017 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/login/ui/lock_contents_view.h"
 
+#include "ash/login/lock_screen_controller.h"
+#include "ash/session/session_controller.h"
+#include "ash/shell.h"
 #include "base/strings/utf_string_conversions.h"
 #include "ui/views/background.h"
 #include "ui/views/border.h"
 #include "ui/views/layout/box_layout.h"
 
 namespace ash {
 
 LockContentsView::LockContentsView() {
   auto* layout = new views::BoxLayout(views::BoxLayout::kVertical, 0, 0, 0);
   SetLayoutManager(layout);
 
   views::Label* label = new views::Label();
   label->SetBorder(views::CreateEmptyBorder(2, 3, 4, 5));
   label->set_background(views::Background::CreateThemedSolidBackground(
       label, ui::NativeTheme::kColorId_BubbleBackground));
   label->SetText(base::ASCIIToUTF16("User"));
   AddChildView(label);
 
   unlock_button_ =
       views::MdTextButton::Create(this, base::ASCIIToUTF16("Unlock"));
   AddChildView(unlock_button_);
 }
 
 LockContentsView::~LockContentsView() {}
 
 void LockContentsView::ButtonPressed(views::Button* sender,
                                      const ui::Event& event) {
   DCHECK(unlock_button_ == sender);
 
-  // TODO: Run mojo call that talks to backend which unlocks the device.
-  NOTIMPLEMENTED();
+  // TODO: user index shouldn't be hard coded here. Complete the implementation
+  // below.
+  const int kUserIndex = 0;

[James Cook, 2017/05/15 21:15:00]

super nit: When we're using a const local just to provide a nice name for a
variable, I prefer |user_index|.

[xiaoyinh(OOO Sep 11-29), 2017/05/16 17:32:50]

Done.

+  SessionController* session_controller = Shell::Get()->session_controller();
+  const mojom::UserSession* const user_session =
+      session_controller->GetUserSession(kUserIndex);

[James Cook, 2017/05/15 21:15:00]

nit: Just inline the call to Shell::Get()->session_controller() here since you
only use the pointer once.

[xiaoyinh(OOO Sep 11-29), 2017/05/16 17:32:50]

Done.

+  Shell::Get()->lock_screen_controller()->AuthenticateUser(
+      user_session->account_id, std::string(),
+      false /* authenticated_by_pin */);

[James Cook, 2017/05/15 21:15:00]

Thanks for documenting what false means here! It makes it easy for me to read.

 }
 
 }  // namespace ash