capture_mode: Skeleton

This CL adds the initial skeleton for the Capture Mode feature.
Future CLs will implement the actual functionality.

BUG=1105227

Change-Id: I2d8d61aa431b6bd9599e8cec65d4836a42eee695
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2327855
Commit-Queue: Ahmed Fakhry <afakhry@chromium.org>
Reviewed-by: James Cook <jamescook@chromium.org>
Cr-Commit-Position: refs/heads/master@{#793367}

ash/BUILD.gn

@@ -49,6 +49,7 @@ component("ash") {
     "public/cpp/autotest_ambient_api.h",
     "public/cpp/autotest_desks_api.h",
     "public/cpp/autotest_private_api_utils.h",
+    "public/cpp/capture_mode_delegate.h",
     "public/cpp/debug_utils.h",
     "public/cpp/docked_magnifier_controller.h",
     "public/cpp/event_rewriter_controller.h",
@@ -250,6 +251,8 @@ component("ash") {
     "bluetooth_devices_observer.h",
     "cancel_mode.cc",
     "cancel_mode.h",
+    "capture_mode/capture_mode_controller.cc",
+    "capture_mode/capture_mode_controller.h",
     "clipboard/clipboard_history.cc",
     "clipboard/clipboard_history.h",
     "clipboard/clipboard_history_controller.cc",
@@ -2291,6 +2294,8 @@ static_library("test_support") {
     "assistant/test/test_assistant_web_view.h",
     "assistant/test/test_assistant_web_view_factory.cc",
     "assistant/test/test_assistant_web_view_factory.h",
+    "capture_mode/test_capture_mode_delegate.cc",
+    "capture_mode/test_capture_mode_delegate.h",
     "display/display_configuration_controller_test_api.cc",
     "display/display_configuration_controller_test_api.h",
     "display/mirror_window_test_api.cc",

ash/capture_mode/OWNERS

@@ -0,0 +1,3 @@
+afakhry@chromium.org
+
+# COMPONENT: UI>Shell>ScreenCapture

ash/capture_mode/capture_mode_controller.cc

@@ -0,0 +1,53 @@
+// Copyright 2020 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/capture_mode/capture_mode_controller.h"
+
+#include <utility>
+
+#include "base/check.h"
+#include "base/check_op.h"
+
+namespace ash {
+
+namespace {
+
+CaptureModeController* g_instance = nullptr;
+
+}  // namespace
+
+CaptureModeController::CaptureModeController(
+    std::unique_ptr<CaptureModeDelegate> delegate)
+    : delegate_(std::move(delegate)) {
+  DCHECK_EQ(g_instance, nullptr);
+  g_instance = this;
+}
+
+CaptureModeController::~CaptureModeController() {
+  DCHECK_EQ(g_instance, this);
+  g_instance = nullptr;
+}
+
+// static
+CaptureModeController* CaptureModeController::Get() {
+  DCHECK(g_instance);
+  return g_instance;
+}
+
+void CaptureModeController::Start() {
+  StartWith(type_, source_);
+}
+
+void CaptureModeController::StartWith(CaptureModeType type,
+                                      CaptureModeSource source) {
+  type_ = type;
+  source_ = source;
+  // TODO(afakhry): Fill in here.
+}
+
+void CaptureModeController::Stop() {
+  // TODO(afakhry): Fill in here.
+}
+
+}  // namespace ash

ash/capture_mode/capture_mode_controller.h

@@ -0,0 +1,58 @@
+// Copyright 2020 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.
+
+#ifndef ASH_CAPTURE_MODE_CAPTURE_MODE_CONTROLLER_H_
+#define ASH_CAPTURE_MODE_CAPTURE_MODE_CONTROLLER_H_
+
+#include <memory>
+
+#include "ash/public/cpp/capture_mode_delegate.h"
+
+namespace ash {
+
+// Defines the capture type Capture Mode is currently using.
+enum class CaptureModeType {
+  kImage,
+  kVideo,
+};
+
+// Defines the source of the capture used by Capture Mode.
+enum class CaptureModeSource {
+  kFullscreen,
+  kRegion,
+  kWindow,
+};
+
+// Controls starting and ending a Capture Mode session and its behavior.
+class CaptureModeController {
+ public:
+  explicit CaptureModeController(std::unique_ptr<CaptureModeDelegate> delegate);
+  CaptureModeController(const CaptureModeController&) = delete;
+  CaptureModeController& operator=(const CaptureModeController&) = delete;
+  ~CaptureModeController();
+
+  // Convenience function to get the controller instance, which is created and
+  // owned by Shell.
+  static CaptureModeController* Get();
+
+  // Starts a new capture session with the most-recently used |type_| and
+  // |source_|.
+  void Start();
+
+  // Starts a new capture session with the specific given |type| and |source|.
+  void StartWith(CaptureModeType type, CaptureModeSource source);
+
+  // Stops an existing capture session.
+  void Stop();
+
+ private:
+  std::unique_ptr<CaptureModeDelegate> delegate_;
+
+  CaptureModeType type_ = CaptureModeType::kImage;
+  CaptureModeSource source_ = CaptureModeSource::kRegion;
+};
+
+}  // namespace ash
+
+#endif  // ASH_CAPTURE_MODE_CAPTURE_MODE_CONTROLLER_H_

ash/capture_mode/test_capture_mode_delegate.cc

@@ -0,0 +1,16 @@
+// Copyright 2020 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/capture_mode/test_capture_mode_delegate.h"
+
+#include "base/files/file_path.h"
+
+namespace ash {
+
+base::FilePath TestCaptureModeDelegate::GetActiveUserDownloadsDir() const {
+  // TODO(afakhry): Add proper code to enable testing.
+  return base::FilePath();
+}
+
+}  // namespace ash

ash/capture_mode/test_capture_mode_delegate.h

@@ -0,0 +1,25 @@
+// Copyright 2020 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.
+
+#ifndef ASH_CAPTURE_MODE_TEST_CAPTURE_MODE_DELEGATE_H_
+#define ASH_CAPTURE_MODE_TEST_CAPTURE_MODE_DELEGATE_H_
+
+#include "ash/public/cpp/capture_mode_delegate.h"
+
+namespace ash {
+
+class TestCaptureModeDelegate : public CaptureModeDelegate {
+ public:
+  TestCaptureModeDelegate() = default;
+  TestCaptureModeDelegate(const TestCaptureModeDelegate&) = delete;
+  TestCaptureModeDelegate& operator=(const TestCaptureModeDelegate&) = delete;
+  ~TestCaptureModeDelegate() override = default;
+
+  // CaptureModeDelegate:
+  base::FilePath GetActiveUserDownloadsDir() const override;
+};
+
+}  // namespace ash
+
+#endif  // ASH_CAPTURE_MODE_TEST_CAPTURE_MODE_DELEGATE_H_

ash/public/cpp/ash_features.cc

@@ -19,6 +19,9 @@ const base::Feature kAllowAmbientEQ{"AllowAmbientEQ",
 const base::Feature kAutoNightLight{"AutoNightLight",
                                     base::FEATURE_DISABLED_BY_DEFAULT};
 
+const base::Feature kCaptureMode{"CaptureMode",
+                                 base::FEATURE_DISABLED_BY_DEFAULT};
+
 const base::Feature kContextualNudges{"ContextualNudges",
                                       base::FEATURE_ENABLED_BY_DEFAULT};
 
@@ -147,6 +150,10 @@ bool IsAutoNightLightEnabled() {
   return base::FeatureList::IsEnabled(kAutoNightLight);
 }
 
+bool IsCaptureModeEnabled() {
+  return base::FeatureList::IsEnabled(kCaptureMode);
+}
+
 bool IsHideArcMediaNotificationsEnabled() {
   return base::FeatureList::IsEnabled(kMediaSessionNotification) &&
          base::FeatureList::IsEnabled(kHideArcMediaNotifications);

ash/public/cpp/ash_features.h

@@ -21,6 +21,10 @@ ASH_PUBLIC_EXPORT extern const base::Feature kAllowAmbientEQ;
 // certain devices.
 ASH_PUBLIC_EXPORT extern const base::Feature kAutoNightLight;
 
+// Enables the Capture Mode feature which is an enhanced screenshot and screen
+// capture user experience.
+ASH_PUBLIC_EXPORT extern const base::Feature kCaptureMode;
+
 // Enables contextual nudges for gesture education.
 ASH_PUBLIC_EXPORT extern const base::Feature kContextualNudges;
 
@@ -176,6 +180,8 @@ ASH_PUBLIC_EXPORT bool IsPerDeskShelfEnabled();
 
 ASH_PUBLIC_EXPORT bool IsAutoNightLightEnabled();
 
+ASH_PUBLIC_EXPORT bool IsCaptureModeEnabled();
+
 ASH_PUBLIC_EXPORT bool IsHideArcMediaNotificationsEnabled();
 
 ASH_PUBLIC_EXPORT bool IsKeyboardShortcutViewerAppEnabled();

ash/public/cpp/capture_mode_delegate.h

@@ -0,0 +1,30 @@
+// Copyright 2020 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.
+
+#ifndef ASH_PUBLIC_CPP_CAPTURE_MODE_DELEGATE_H_
+#define ASH_PUBLIC_CPP_CAPTURE_MODE_DELEGATE_H_
+
+#include "ash/public/cpp/ash_public_export.h"
+
+namespace base {
+class FilePath;
+}  // namespace base
+
+namespace ash {
+
+// Defines the interface for the delegate of CaptureModeController, that can be
+// implemented by an ash client (e.g. Chrome). The CaptureModeController owns
+// the instance of this delegate.
+class ASH_PUBLIC_EXPORT CaptureModeDelegate {
+ public:
+  virtual ~CaptureModeDelegate() = default;
+
+  // Returns the path to the active user's downloads directory. This will never
+  // be called if the user is not logged in.
+  virtual base::FilePath GetActiveUserDownloadsDir() const = 0;
+};
+
+}  // namespace ash
+
+#endif  // ASH_PUBLIC_CPP_CAPTURE_MODE_DELEGATE_H_

ash/shell.cc

@@ -23,6 +23,7 @@
 #include "ash/app_list/app_list_controller_impl.h"
 #include "ash/assistant/assistant_controller_impl.h"
 #include "ash/autoclick/autoclick_controller.h"
+#include "ash/capture_mode/capture_mode_controller.h"
 #include "ash/clipboard/clipboard_history_controller.h"
 #include "ash/dbus/ash_dbus_services.h"
 #include "ash/detachable_base/detachable_base_handler.h"
@@ -917,6 +918,11 @@ void Shell::Init(
   accessibility_controller_ = std::make_unique<AccessibilityControllerImpl>();
   toast_manager_ = std::make_unique<ToastManagerImpl>();
 
+  if (features::IsCaptureModeEnabled()) {
+    capture_mode_controller_ = std::make_unique<CaptureModeController>(
+        shell_delegate_->CreateCaptureModeDelegate());
+  }
+
   // Accelerometer file reader starts listening to tablet mode controller.
   AccelerometerReader::GetInstance()->StartListenToTabletModeController();
 

ash/shell.h

@@ -95,6 +95,7 @@ class BluetoothNotificationController;
 class BluetoothPowerController;
 class BrightnessControlDelegate;
 class AshColorProvider;
+class CaptureModeController;
 class CrosDisplayConfig;
 class DesksController;
 class DetachableBaseHandler;
@@ -706,6 +707,7 @@ class ASH_EXPORT Shell : public SessionObserver,
   std::unique_ptr<ShelfController> shelf_controller_;
   std::unique_ptr<ShelfWindowWatcher> shelf_window_watcher_;
   std::unique_ptr<ShellDelegate> shell_delegate_;
+  std::unique_ptr<CaptureModeController> capture_mode_controller_;
   std::unique_ptr<ShutdownControllerImpl> shutdown_controller_;
   std::unique_ptr<SystemNotificationController> system_notification_controller_;
   std::unique_ptr<SystemTrayModel> system_tray_model_;

ash/shell_delegate.h

@@ -30,6 +30,7 @@ class OSExchangeData;
 namespace ash {
 
 class AccessibilityDelegate;
+class CaptureModeDelegate;
 class ScreenshotDelegate;
 class BackGestureContextualNudgeDelegate;
 class BackGestureContextualNudgeController;
@@ -38,12 +39,16 @@ class BackGestureContextualNudgeController;
 class ASH_EXPORT ShellDelegate {
  public:
   // The Shell owns the delegate.
-  virtual ~ShellDelegate() {}
+  virtual ~ShellDelegate() = default;
 
   // Returns true if |window| can be shown for the delegate's concept of current
   // user.
   virtual bool CanShowWindowForUser(const aura::Window* window) const = 0;
 
+  // Creates and returns the delegate of the Capture Mode feature.
+  virtual std::unique_ptr<CaptureModeDelegate> CreateCaptureModeDelegate()
+      const = 0;
+
   // TODO(jamescook): Replace with a mojo-compatible interface.
   virtual std::unique_ptr<ScreenshotDelegate> CreateScreenshotDelegate() = 0;
 

ash/test_shell_delegate.cc

@@ -4,7 +4,10 @@
 
 #include "ash/test_shell_delegate.h"
 
+#include <memory>
+
 #include "ash/accessibility/default_accessibility_delegate.h"
+#include "ash/capture_mode/test_capture_mode_delegate.h"
 #include "ash/system/tray/system_tray_notifier.h"
 #include "ash/test_screenshot_delegate.h"
 #include "ash/wm/gestures/back_gesture/test_back_gesture_contextual_nudge_delegate.h"
@@ -20,6 +23,11 @@ bool TestShellDelegate::CanShowWindowForUser(const aura::Window* window) const {
   return true;
 }
 
+std::unique_ptr<CaptureModeDelegate>
+TestShellDelegate::CreateCaptureModeDelegate() const {
+  return std::make_unique<TestCaptureModeDelegate>();
+}
+
 std::unique_ptr<ScreenshotDelegate>
 TestShellDelegate::CreateScreenshotDelegate() {
   return std::make_unique<TestScreenshotDelegate>();

ash/test_shell_delegate.h

@@ -31,6 +31,8 @@ class TestShellDelegate : public ShellDelegate {
 
   // Overridden from ShellDelegate:
   bool CanShowWindowForUser(const aura::Window* window) const override;
+  std::unique_ptr<CaptureModeDelegate> CreateCaptureModeDelegate()
+      const override;
   std::unique_ptr<ScreenshotDelegate> CreateScreenshotDelegate() override;
   AccessibilityDelegate* CreateAccessibilityDelegate() override;
   std::unique_ptr<BackGestureContextualNudgeDelegate>

chrome/browser/ui/BUILD.gn

@@ -1821,6 +1821,8 @@ static_library("ui") {
       "ash/chrome_accessibility_delegate.h",
       "ash/chrome_browser_main_extra_parts_ash.cc",
       "ash/chrome_browser_main_extra_parts_ash.h",
+      "ash/chrome_capture_mode_delegate.cc",
+      "ash/chrome_capture_mode_delegate.h",
       "ash/chrome_launcher_prefs.cc",
       "ash/chrome_launcher_prefs.h",
       "ash/chrome_new_window_client.cc",

chrome/browser/ui/ash/chrome_capture_mode_delegate.cc

@@ -0,0 +1,21 @@
+// Copyright 2020 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/chrome_capture_mode_delegate.h"
+
+#include "base/files/file_path.h"
+#include "chrome/browser/download/download_prefs.h"
+#include "chrome/browser/profiles/profile_manager.h"
+#include "chromeos/login/login_state/login_state.h"
+
+ChromeCaptureModeDelegate::ChromeCaptureModeDelegate() = default;
+
+ChromeCaptureModeDelegate::~ChromeCaptureModeDelegate() = default;
+
+base::FilePath ChromeCaptureModeDelegate::GetActiveUserDownloadsDir() const {
+  DCHECK(chromeos::LoginState::Get()->IsUserLoggedIn());
+  DownloadPrefs* download_prefs =
+      DownloadPrefs::FromBrowserContext(ProfileManager::GetActiveUserProfile());
+  return download_prefs->DownloadPath();
+}