Fix Volume slider is captured in screenshot done in touchview mode

ash/wm/power_button_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/wm/power_button_controller.h"
 
 #include "ash/common/accelerators/accelerator_controller.h"
 #include "ash/common/ash_switches.h"
 #include "ash/common/session/session_state_delegate.h"
 #include "ash/common/shell_window_ids.h"
+#include "ash/common/system/tray/system_tray_notifier.h"
 #include "ash/common/wm/maximize_mode/maximize_mode_controller.h"
 #include "ash/common/wm_shell.h"
 #include "ash/shell.h"
 #include "ash/wm/lock_state_controller.h"
 #include "ash/wm/session_state_animator.h"
 #include "base/command_line.h"
 #include "ui/aura/window_event_dispatcher.h"
 #include "ui/display/types/display_snapshot.h"
 #include "ui/events/event_handler.h"
 #include "ui/wm/core/compound_event_filter.h"
 
 #if defined(OS_CHROMEOS)
+#include "chromeos/audio/cras_audio_handler.h"
 #include "chromeos/dbus/dbus_thread_manager.h"
 #endif
 
 namespace ash {
 
 PowerButtonController::PowerButtonController(LockStateController* controller)
     : power_button_down_(false),
       lock_button_down_(false),
       volume_down_pressed_(false),
+#if defined(OS_CHROMEOS)
+      volume_percent_before_screenshot_(0),
+#endif
       brightness_is_zero_(false),
       internal_display_off_and_external_display_on_(false),
       has_legacy_power_button_(
           base::CommandLine::ForCurrentProcess()->HasSwitch(
               switches::kAuraLegacyPowerButton)),
 #if defined(OS_CHROMEOS)
       enable_quick_lock_(base::CommandLine::ForCurrentProcess()->HasSwitch(
           switches::kAshEnableTouchView)),
 #else
       enable_quick_lock_(false),
@@ skipping 31 matching lines @@
   // Avoid starting the lock/shutdown sequence if the power button is pressed
   // while the screen is off (http://crbug.com/128451), unless an external
   // display is still on (http://crosbug.com/p/24912).
   if (brightness_is_zero_ && !internal_display_off_and_external_display_on_)
     return;
 
   if (volume_down_pressed_ && down &&
       WmShell::Get()
           ->maximize_mode_controller()
           ->IsMaximizeModeWindowManagerEnabled()) {
-    WmShell::Get()->accelerator_controller()->PerformActionIfEnabled(
-        TAKE_SCREENSHOT);
+    // Notify that maximize mode screenshot is going to be taken. Receiver does
+    // preparation work.
+    WmShell* wm_shell = WmShell::Get();
+    wm_shell->system_tray_notifier()->NotifyTakingScreenshotInMaximizeMode();

[James Cook, 2016/08/01 16:51:46]

This is fine.

+    wm_shell->accelerator_controller()->PerformActionIfEnabled(TAKE_SCREENSHOT);
+
+#if defined(OS_CHROMEOS)
+    // Restore volume.
+    chromeos::CrasAudioHandler* audio_handler =
+        chromeos::CrasAudioHandler::Get();
+    audio_handler->SetOutputVolumePercentWithoutNotifyingObservers(
+        volume_percent_before_screenshot_);
+#endif
     return;
   }
 
   const SessionStateDelegate* session_state_delegate =
       WmShell::Get()->GetSessionStateDelegate();
   if (has_legacy_power_button_) {
     // If power button releases won't get reported correctly because we're not
     // running on official hardware, just lock the screen or shut down
     // immediately.
     if (down) {
@@ skipping 49 matching lines @@
   if (power_button_down_)
     return;
 
   if (down)
     controller_->StartLockAnimation(false);
   else
     controller_->CancelLockAnimation();
 }
 
 void PowerButtonController::OnKeyEvent(ui::KeyEvent* event) {
-  if (event->key_code() == ui::VKEY_VOLUME_DOWN)
+  if (event->key_code() == ui::VKEY_VOLUME_DOWN) {
     volume_down_pressed_ = event->type() == ui::ET_KEY_PRESSED;
+#if defined(OS_CHROMEOS)
+    if (!event->is_repeat()) {
+      chromeos::CrasAudioHandler* audio_handler =
+          chromeos::CrasAudioHandler::Get();
+      volume_percent_before_screenshot_ =
+          audio_handler->GetOutputVolumePercent();
+    }
+#endif
+  }
 }
 
 #if defined(OS_CHROMEOS)
 void PowerButtonController::OnDisplayModeChanged(
     const ui::DisplayConfigurator::DisplayStateList& display_states) {
   bool internal_display_off = false;
   bool external_display_on = false;
   for (const ui::DisplaySnapshot* display : display_states) {
     if (display->type() == ui::DISPLAY_CONNECTION_TYPE_INTERNAL) {
       if (!display->current_mode())
         internal_display_off = true;
     } else if (display->current_mode()) {
       external_display_on = true;
     }
   }
   internal_display_off_and_external_display_on_ =
       internal_display_off && external_display_on;
 }
 
 void PowerButtonController::PowerButtonEventReceived(
     bool down,
     const base::TimeTicks& timestamp) {
   OnPowerButtonEvent(down, timestamp);
 }
 #endif  // defined(OS_CHROMEOS)
 
 }  // namespace ash