wallpaper refactoring: Reimplement SetPolicyWallpaper

A few differences with the current implementation:

1) Currently there're both |WallpaperManager::OnPolicySet| and
   |OnPolicyFetched|. |OnPolicySet| merely labels the wallpaper
   as POLICY type to prevent potential wallpaper changes. This results
   in a temporary inconsistency between the actual wallpaper and its
   type. In this version this method is deleted. (ie, if policy fetch
   never succeeds, WallpaperController won't know about the policy.)

2) Currently |OnPolicyCleared| only sets the type back to DEFAULT
   without deleting the policy wallpaper file. This doesn't result in
   visible bugs, but it's better to delete the files and explicitly
   calls SetDefaultWallpaper for this user.

3) The existing tests in wallpaper_manager_policy_browsertest.cc stay
   unchanged in this CL. But they may be moved to a different place
   later.

Test: Verified on Admin console, no conflict with device policy.
Bug: 779221, 800182
Change-Id: Ibb3fa38ddc19b095bfd684fe2fa6e500d7a580b4
Reviewed-on: https://chromium-review.googlesource.com/845262Reviewed-by: Mitsuru Oshima <oshima@chromium.org>
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Reviewed-by: Xiaoqian Dai <xdai@chromium.org>
Commit-Queue: Wenzhao (Colin) Zang <wzang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#531301}

ash/public/interfaces/wallpaper.mojom

@@ -81,13 +81,12 @@ interface WallpaperController {
        mojo.common.mojom.FilePath chromeos_custom_wallpapers_path,
        bool is_device_wallpaper_policy_enforced);
 
-  // Sets wallpaper from policy or from a local file. Saves the custom wallpaper
-  // to file, posts task to generate thumbnail and updates local state.
+  // Sets wallpaper from a local file. Saves the custom wallpaper to file, posts
+  // task to generate thumbnail and updates local state.
   // |user_info|: The user's information related to wallpaper.
   // |wallpaper_files_id|: The file id for user_info.account_id.
   // |file_name|: The name of the wallpaper file.
   // |layout|: The layout of the wallpaper, used for wallpaper resizing.
-  // |type|: The type of the wallpaper, e.g., default, policy etc.
   // |image|: The wallpaper image.
   // |show_wallpaper|: If false, don't show the new wallpaper now but only
   //                   update cache.
@@ -95,7 +94,6 @@ interface WallpaperController {
                      string wallpaper_files_id,
                      string file_name,
                      WallpaperLayout layout,
-                     WallpaperType type,
                      skia.mojom.Bitmap image,
                      bool show_wallpaper);
 
@@ -134,6 +132,17 @@ interface WallpaperController {
                                 mojo.common.mojom.FilePath file_path,
                                 mojo.common.mojom.FilePath resized_directory);
 
+  // Sets wallpaper from policy. If the user has logged in, show the policy
+  // wallpaper immediately, otherwise, the policy wallpaper will be shown the
+  // next time |ShowUserWallpaper| is called. Note: it is different from device
+  // policy.
+  // |user_info|: The user's information related to wallpaper.
+  // |wallpaper_files_id|: The file id for user_info.account_id.
+  // |data|: The data used to decode the image.
+  SetPolicyWallpaper(WallpaperUserInfo user_info,
+                     string wallpaper_files_id,
+                     string data);
+
   // Sets whether device wallpaper policy is enforced on this device. Updates/
   // clears the device policy controlled wallpaper if applicable.
   SetDeviceWallpaperPolicyEnforced(bool enforced);
@@ -161,6 +170,15 @@ interface WallpaperController {
   // |wallpaper_files_id|: The file id for user_info.account_id.
   RemoveUserWallpaper(WallpaperUserInfo user_info, string wallpaper_files_id);
 
+  // Removes all of the user's saved wallpapers and related info if the
+  // wallpaper was set by |SetPolicyWallpaper|. In addition, sets the user's
+  // wallpaper to be the default. If the user has logged in, show the default
+  // wallpaper immediately, otherwise, the default wallpaper will be shown the
+  // next time |ShowUserWallpaper| is called.
+  // |user_info|: The user's information related to wallpaper.
+  // |wallpaper_files_id|: The file id for user_info.account_id.
+  RemovePolicyWallpaper(WallpaperUserInfo user_info, string wallpaper_files_id);
+
   // TODO(crbug.com/776464): This is only used by WallpaperManager. Remove this
   // after WallpaperManager is removed.
   //

ash/wallpaper/wallpaper_controller.cc

@@ -72,6 +72,9 @@ const char kNewWallpaperTypeNodeName[] = "type";
 const char kDeviceWallpaperDir[] = "device_wallpaper";
 const char kDeviceWallpaperFile[] = "device_wallpaper_image.jpg";
 
+// The file name of the policy wallpaper.
+const char kPolicyWallpaperFile[] = "policy-controlled.jpeg";
+
 // How long to wait reloading the wallpaper after the display size has changed.
 constexpr int kWallpaperReloadDelayMs = 100;
 
@@ -179,6 +182,21 @@ ColorProfileType GetColorProfileType(ColorProfile color_profile) {
   return ColorProfileType::DARK_MUTED;
 }
 
+// If |read_is_successful| is true, start decoding the image, which will run
+// |callback| upon completion; if it's false, run |callback| directly with an
+// empty image.
+void OnWallpaperDataRead(LoadedCallback callback,
+                         std::unique_ptr<std::string> data,
+                         bool read_is_successful) {
+  if (!read_is_successful) {
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
+        FROM_HERE,
+        base::BindOnce(std::move(callback), base::Passed(gfx::ImageSkia())));
+  } else {
+    DecodeWallpaper(*data, std::move(callback));
+  }
+}
+
 // Deletes a list of wallpaper files in |file_list|.
 void DeleteWallpaperInList(const std::vector<base::FilePath>& file_list) {
   for (const base::FilePath& path : file_list) {
@@ -524,21 +542,6 @@ void WallpaperController::SetWallpaperFromPath(
   }
 }
 
-// static
-void WallpaperController::DecodeWallpaperIfApplicable(
-    LoadedCallback callback,
-    std::unique_ptr<std::string> data,
-    bool data_is_ready) {
-  // The connector for the mojo service manager is null in unit tests.
-  if (!data_is_ready || !Shell::Get()->shell_delegate()->GetShellConnector()) {
-    base::ThreadTaskRunnerHandle::Get()->PostTask(
-        FROM_HERE,
-        base::BindOnce(std::move(callback), base::Passed(gfx::ImageSkia())));
-  } else {
-    DecodeWallpaper(std::move(data), std::move(callback));
-  }
-}
-
 // static
 gfx::ImageSkia WallpaperController::CreateSolidColorWallpaper() {
   SkBitmap bitmap;
@@ -722,6 +725,7 @@ void WallpaperController::SetCustomizedDefaultWallpaperPaths(
 void WallpaperController::SetWallpaperImage(const gfx::ImageSkia& image,
                                             const WallpaperInfo& info) {
   wallpaper::WallpaperLayout layout = info.layout;
+
   VLOG(1) << "SetWallpaper: image_id="
           << wallpaper::WallpaperResizer::GetImageId(image)
           << " layout=" << layout;
@@ -893,11 +897,15 @@ void WallpaperController::ReadAndDecodeWallpaper(
     scoped_refptr<base::SequencedTaskRunner> task_runner,
     const base::FilePath& file_path) {
   decode_requests_for_testing_.push_back(file_path);
+  if (bypass_decode_for_testing_) {
+    std::move(callback).Run(CreateSolidColorWallpaper());
+    return;
+  }
   std::string* data = new std::string;
   base::PostTaskAndReplyWithResult(
       task_runner.get(), FROM_HERE,
       base::Bind(&base::ReadFileToString, file_path, data),
-      base::Bind(&DecodeWallpaperIfApplicable, std::move(callback),
+      base::Bind(&OnWallpaperDataRead, callback,
                  base::Passed(base::WrapUnique(data))));
 }
 
@@ -1031,7 +1039,7 @@ void WallpaperController::SetArcWallpaper(
   // |has_gaia_account| is unused.
   user_info->has_gaia_account = true;
   SaveAndSetWallpaper(std::move(user_info), wallpaper_files_id, file_name,
-                      image, wallpaper::CUSTOMIZED, layout, show_wallpaper);
+                      wallpaper::CUSTOMIZED, layout, show_wallpaper, image);
 }
 
 bool WallpaperController::GetWallpaperFromCache(const AccountId& account_id,
@@ -1073,22 +1081,13 @@ void WallpaperController::SetCustomWallpaper(
     const std::string& wallpaper_files_id,
     const std::string& file_name,
     wallpaper::WallpaperLayout layout,
-    wallpaper::WallpaperType type,
     const SkBitmap& image,
     bool show_wallpaper) {
-  // TODO(crbug.com/776464): Currently |SetCustomWallpaper| is used by both
-  // CUSTOMIZED and POLICY types, but it's better to separate them: a new
-  // |SetPolicyWallpaper| will be created so that the type parameter can be
-  // removed, and only a single |CanSetUserWallpaper| check is needed here.
-  if ((type != wallpaper::POLICY &&
-       IsPolicyControlled(user_info->account_id, !user_info->is_ephemeral)) ||
-      IsInKioskMode()) {
+  if (!CanSetUserWallpaper(user_info->account_id, !user_info->is_ephemeral))
     return;
-  }
-
   SaveAndSetWallpaper(std::move(user_info), wallpaper_files_id, file_name,
-                      gfx::ImageSkia::CreateFrom1xBitmap(image), type, layout,
-                      show_wallpaper);
+                      wallpaper::CUSTOMIZED, layout, show_wallpaper,
+                      gfx::ImageSkia::CreateFrom1xBitmap(image));
 }
 
 void WallpaperController::SetOnlineWallpaper(
@@ -1147,6 +1146,29 @@ void WallpaperController::SetCustomizedDefaultWallpaper(
   NOTIMPLEMENTED();
 }
 
+void WallpaperController::SetPolicyWallpaper(
+    mojom::WallpaperUserInfoPtr user_info,
+    const std::string& wallpaper_files_id,
+    const std::string& data) {
+  // There is no visible wallpaper in kiosk mode.
+  if (IsInKioskMode())
+    return;
+
+  // Updates the screen only when the user has logged in.
+  const bool show_wallpaper =
+      Shell::Get()->session_controller()->IsActiveUserSessionStarted();
+  LoadedCallback callback =
+      base::Bind(&WallpaperController::SaveAndSetWallpaper,
+                 weak_factory_.GetWeakPtr(), base::Passed(&user_info),
+                 wallpaper_files_id, kPolicyWallpaperFile, wallpaper::POLICY,
+                 wallpaper::WALLPAPER_LAYOUT_CENTER_CROPPED, show_wallpaper);
+
+  if (bypass_decode_for_testing_)
+    std::move(callback).Run(CreateSolidColorWallpaper());
+  else
+    DecodeWallpaper(data, std::move(callback));
+}
+
 void WallpaperController::SetDeviceWallpaperPolicyEnforced(bool enforced) {
   bool previous_enforced = is_device_wallpaper_policy_enforced_;
   is_device_wallpaper_policy_enforced_ = enforced;
@@ -1285,6 +1307,19 @@ void WallpaperController::RemoveUserWallpaper(
   RemoveUserWallpaperImpl(user_info->account_id, wallpaper_files_id);
 }
 
+void WallpaperController::RemovePolicyWallpaper(
+    mojom::WallpaperUserInfoPtr user_info,
+    const std::string& wallpaper_files_id) {
+  DCHECK(IsPolicyControlled(user_info->account_id, !user_info->is_ephemeral));
+  // Updates the screen only when the user has logged in.
+  const bool show_wallpaper =
+      Shell::Get()->session_controller()->IsActiveUserSessionStarted();
+  // Removes the wallpaper info so that the user is no longer policy controlled,
+  // otherwise setting default wallpaper is not allowed.
+  RemoveUserWallpaperInfo(user_info->account_id, !user_info->is_ephemeral);
+  SetDefaultWallpaper(std::move(user_info), wallpaper_files_id, show_wallpaper);
+}
+
 void WallpaperController::SetWallpaper(const SkBitmap& wallpaper,
                                        const WallpaperInfo& info) {
   if (wallpaper.isNull())
@@ -1563,7 +1598,7 @@ void WallpaperController::OnDefaultWallpaperDecoded(
   }
 
   if (show_wallpaper) {
-    // 1x1 wallpaper is actually solid color, so it should be stretched.
+    // 1x1 wallpaper should be stretched.
     if (cached_default_wallpaper_.image.width() == 1 &&
         cached_default_wallpaper_.image.height() == 1) {
       layout = wallpaper::WALLPAPER_LAYOUT_STRETCH;
@@ -1578,14 +1613,15 @@ void WallpaperController::SaveAndSetWallpaper(
     mojom::WallpaperUserInfoPtr user_info,
     const std::string& wallpaper_files_id,
     const std::string& file_name,
-    const gfx::ImageSkia& image,
     wallpaper::WallpaperType type,
     wallpaper::WallpaperLayout layout,
-    bool show_wallpaper) {
-  // Empty image indicates decode failure. Use default wallpaper in this case.
+    bool show_wallpaper,
+    const gfx::ImageSkia& image) {
+  // If the image of the new wallpaper is empty, the current wallpaper is still
+  // kept instead of reverting to the default.
   if (image.isNull()) {
-    SetDefaultWallpaperImpl(user_info->account_id, user_info->type,
-                            show_wallpaper);
+    LOG(ERROR) << "The wallpaper image is empty due to a decoding failure, or "
+                  "the client provided an empty image.";
     return;
   }
 

ash/wallpaper/wallpaper_controller.h

@@ -182,16 +182,6 @@ class ASH_EXPORT WallpaperController
       const scoped_refptr<base::SingleThreadTaskRunner>& reply_task_runner,
       base::WeakPtr<WallpaperController> weak_ptr);
 
-  // If |data_is_ready| is true, start decoding the image, which will run
-  // |callback| upon completion; if it's false, run |callback| immediately with
-  // an empty image.
-  // TODO(crbug.com/776464): Mash and some unit tests can't use this decoder
-  // because it depends on the Shell instance. Make it work after all the
-  // decoding code is moved to //ash.
-  static void DecodeWallpaperIfApplicable(LoadedCallback callback,
-                                          std::unique_ptr<std::string> data,
-                                          bool data_is_ready);
-
   // Creates a 1x1 solid color image to be used as the backup default wallpaper.
   static gfx::ImageSkia CreateSolidColorWallpaper();
 
@@ -306,8 +296,8 @@ class ASH_EXPORT WallpaperController
                                 bool compare_layouts,
                                 wallpaper::WallpaperLayout layout) const;
 
-  // Reads image from |file_path| on disk, and calls
-  // |DecodeWallpaperIfApplicable| with the result of |ReadFileToString|.
+  // Reads image from |file_path| on disk, and calls |OnWallpaperDataRead|
+  // with the result of |ReadFileToString|.
   void ReadAndDecodeWallpaper(
       LoadedCallback callback,
       scoped_refptr<base::SequencedTaskRunner> task_runner,
@@ -380,7 +370,6 @@ class ASH_EXPORT WallpaperController
                           const std::string& wallpaper_files_id,
                           const std::string& file_name,
                           wallpaper::WallpaperLayout layout,
-                          wallpaper::WallpaperType type,
                           const SkBitmap& image,
                           bool show_wallpaper) override;
   void SetOnlineWallpaper(mojom::WallpaperUserInfoPtr user_info,
@@ -395,6 +384,9 @@ class ASH_EXPORT WallpaperController
       const GURL& wallpaper_url,
       const base::FilePath& file_path,
       const base::FilePath& resized_directory) override;
+  void SetPolicyWallpaper(mojom::WallpaperUserInfoPtr user_info,
+                          const std::string& wallpaper_files_id,
+                          const std::string& data) override;
   void SetDeviceWallpaperPolicyEnforced(bool enforced) override;
   void UpdateCustomWallpaperLayout(mojom::WallpaperUserInfoPtr user_info,
                                    wallpaper::WallpaperLayout layout) override;
@@ -406,6 +398,8 @@ class ASH_EXPORT WallpaperController
   void ShowSigninWallpaper() override;
   void RemoveUserWallpaper(mojom::WallpaperUserInfoPtr user_info,
                            const std::string& wallpaper_files_id) override;
+  void RemovePolicyWallpaper(mojom::WallpaperUserInfoPtr user_info,
+                             const std::string& wallpaper_files_id) override;
   void SetWallpaper(const SkBitmap& wallpaper,
                     const wallpaper::WallpaperInfo& wallpaper_info) override;
   void AddObserver(mojom::WallpaperObserverAssociatedPtrInfo observer) override;
@@ -486,10 +480,10 @@ class ASH_EXPORT WallpaperController
   void SaveAndSetWallpaper(mojom::WallpaperUserInfoPtr user_info,
                            const std::string& wallpaper_files_id,
                            const std::string& file_name,
-                           const gfx::ImageSkia& image,
                            wallpaper::WallpaperType type,
                            wallpaper::WallpaperLayout layout,
-                           bool show_wallpaper);
+                           bool show_wallpaper,
+                           const gfx::ImageSkia& image);
 
   // A wrapper of |ReadAndDecodeWallpaper| used in |SetWallpaperFromPath|.
   void StartDecodeFromPath(const AccountId& account_id,
@@ -622,6 +616,9 @@ class ASH_EXPORT WallpaperController
 
   std::unique_ptr<ui::CompositorLock> compositor_lock_;
 
+  // If true, use a solid color wallpaper as if it is the decoded image.
+  bool bypass_decode_for_testing_ = false;
+
   // Tracks how many wallpapers have been set.
   int wallpaper_count_for_testing_ = 0;
 

ash/wallpaper/wallpaper_controller_unittest.cc

@@ -465,6 +465,8 @@ class WallpaperControllerTest : public AshTestBase {
 
   int GetWallpaperCount() { return controller_->wallpaper_count_for_testing_; }
 
+  void SetBypassDecode() { controller_->bypass_decode_for_testing_ = true; }
+
   void ClearWallpaperCount() { controller_->wallpaper_count_for_testing_ = 0; }
 
   void ClearDecodeFilePaths() {
@@ -829,14 +831,13 @@ TEST_F(WallpaperControllerTest, MojoWallpaperObserverTest) {
 TEST_F(WallpaperControllerTest, SetCustomWallpaper) {
   gfx::ImageSkia image = CreateImage(640, 480, kWallpaperColor);
   WallpaperLayout layout = WALLPAPER_LAYOUT_CENTER;
-  wallpaper::WallpaperType type = wallpaper::CUSTOMIZED;
 
   SimulateUserLogin(user_1);
 
   // Verify the wallpaper is set successfully and wallpaper info is updated.
-  controller_->SetCustomWallpaper(
-      InitializeUser(account_id_1), wallpaper_files_id_1, file_name_1, layout,
-      type, *image.bitmap(), true /*show_wallpaper=*/);
+  controller_->SetCustomWallpaper(InitializeUser(account_id_1),
+                                  wallpaper_files_id_1, file_name_1, layout,
+                                  *image.bitmap(), true /*show_wallpaper=*/);
   RunAllTasksUntilIdle();
   EXPECT_EQ(1, GetWallpaperCount());
   EXPECT_EQ(controller_->GetWallpaperType(), wallpaper::CUSTOMIZED);
@@ -845,14 +846,14 @@ TEST_F(WallpaperControllerTest, SetCustomWallpaper) {
                                                 true /* is_persistent */));
   wallpaper::WallpaperInfo expected_wallpaper_info(
       base::FilePath(wallpaper_files_id_1).Append(file_name_1).value(), layout,
-      type, base::Time::Now().LocalMidnight());
+      wallpaper::CUSTOMIZED, base::Time::Now().LocalMidnight());
   EXPECT_EQ(wallpaper_info, expected_wallpaper_info);
 
   // Verify that the wallpaper is not set when |show_wallpaper| is false, but
   // wallpaper info is updated properly.
-  controller_->SetCustomWallpaper(
-      InitializeUser(account_id_1), wallpaper_files_id_1, file_name_1, layout,
-      type, *image.bitmap(), true /*show_wallpaper=*/);
+  controller_->SetCustomWallpaper(InitializeUser(account_id_1),
+                                  wallpaper_files_id_1, file_name_1, layout,
+                                  *image.bitmap(), true /*show_wallpaper=*/);
   RunAllTasksUntilIdle();
   EXPECT_EQ(0, GetWallpaperCount());
   EXPECT_TRUE(controller_->GetUserWallpaperInfo(account_id_1, &wallpaper_info,
@@ -891,6 +892,73 @@ TEST_F(WallpaperControllerTest, SetOnlineWallpaper) {
   EXPECT_EQ(wallpaper_info, expected_wallpaper_info);
 }
 
+TEST_F(WallpaperControllerTest, SetAndRemovePolicyWallpaper) {
+  SetBypassDecode();
+  // Simulate the login screen.
+  ClearLogin();
+
+  // The user starts with no wallpaper info and is not controlled by policy.
+  wallpaper::WallpaperInfo wallpaper_info;
+  EXPECT_FALSE(controller_->GetUserWallpaperInfo(account_id_1, &wallpaper_info,
+                                                 true /*is_persistent=*/));
+  EXPECT_FALSE(
+      controller_->IsPolicyControlled(account_id_1, true /*is_persistent=*/));
+  // A default wallpaper is shown for the user.
+  controller_->ShowUserWallpaper(InitializeUser(account_id_1));
+  EXPECT_EQ(1, GetWallpaperCount());
+  EXPECT_EQ(controller_->GetWallpaperType(), wallpaper::DEFAULT);
+
+  // Set a policy wallpaper. Verify that the user becomes policy controlled and
+  // the wallpaper info is updated.
+  controller_->SetPolicyWallpaper(InitializeUser(account_id_1),
+                                  wallpaper_files_id_1,
+                                  std::string() /*data=*/);
+  RunAllTasksUntilIdle();
+  EXPECT_TRUE(controller_->GetUserWallpaperInfo(account_id_1, &wallpaper_info,
+                                                true /*is_persistent=*/));
+  wallpaper::WallpaperInfo policy_wallpaper_info(
+      base::FilePath(wallpaper_files_id_1)
+          .Append("policy-controlled.jpeg")
+          .value(),
+      wallpaper::WALLPAPER_LAYOUT_CENTER_CROPPED, wallpaper::POLICY,
+      base::Time::Now().LocalMidnight());
+  EXPECT_EQ(wallpaper_info, policy_wallpaper_info);
+  EXPECT_TRUE(
+      controller_->IsPolicyControlled(account_id_1, true /*is_persistent=*/));
+  // Verify the wallpaper is not updated since the user hasn't logged in.
+  EXPECT_EQ(0, GetWallpaperCount());
+
+  // Log in the user. Verify the policy wallpaper is now being shown.
+  SimulateUserLogin(user_1);
+  controller_->ShowUserWallpaper(InitializeUser(account_id_1));
+  EXPECT_EQ(1, GetWallpaperCount());
+  EXPECT_EQ(controller_->GetWallpaperType(), wallpaper::POLICY);
+
+  // Log out the user and remove the policy wallpaper. Verify the wallpaper
+  // info is reset to default and the user is no longer policy controlled.
+  ClearLogin();
+  controller_->RemovePolicyWallpaper(InitializeUser(account_id_1),
+                                     wallpaper_files_id_1);
+  WaitUntilCustomWallpapersDeleted(account_id_1);
+  EXPECT_TRUE(controller_->GetUserWallpaperInfo(account_id_1, &wallpaper_info,
+                                                true /*is_persistent=*/));
+  wallpaper::WallpaperInfo default_wallpaper_info(
+      std::string(), wallpaper::WALLPAPER_LAYOUT_CENTER_CROPPED,
+      wallpaper::DEFAULT, base::Time::Now().LocalMidnight());
+  EXPECT_EQ(wallpaper_info, default_wallpaper_info);
+  EXPECT_FALSE(
+      controller_->IsPolicyControlled(account_id_1, true /*is_persistent=*/));
+  // Verify the wallpaper is not updated since the user hasn't logged in.
+  EXPECT_EQ(0, GetWallpaperCount());
+  EXPECT_EQ(controller_->GetWallpaperType(), wallpaper::POLICY);
+
+  // Log in the user. Verify the default wallpaper is now being shown.
+  SimulateUserLogin(user_1);
+  controller_->ShowUserWallpaper(InitializeUser(account_id_1));
+  EXPECT_EQ(1, GetWallpaperCount());
+  EXPECT_EQ(controller_->GetWallpaperType(), wallpaper::DEFAULT);
+}
+
 TEST_F(WallpaperControllerTest, SetDefaultWallpaperForRegularAccount) {
   CreateDefaultWallpapers();
   SimulateUserLogin(user_1);
@@ -1064,8 +1132,7 @@ TEST_F(WallpaperControllerTest, IgnoreWallpaperRequestInKioskMode) {
   // |account_id|'s wallpaper info is not updated.
   controller_->SetCustomWallpaper(
       InitializeUser(account_id_1), wallpaper_files_id_1, file_name_1,
-      WALLPAPER_LAYOUT_CENTER, wallpaper::CUSTOMIZED, *image.bitmap(),
-      true /* show_wallpaper */);
+      WALLPAPER_LAYOUT_CENTER, *image.bitmap(), true /*show_wallpaper=*/);
   RunAllTasksUntilIdle();
   EXPECT_EQ(0, GetWallpaperCount());
   wallpaper::WallpaperInfo wallpaper_info;
@@ -1111,8 +1178,7 @@ TEST_F(WallpaperControllerTest, IgnoreWallpaperRequestWhenPolicyIsEnforced) {
   // enforced, and |account_id|'s wallpaper info is not updated.
   controller_->SetCustomWallpaper(
       InitializeUser(account_id_1), wallpaper_files_id_1, file_name_1,
-      WALLPAPER_LAYOUT_CENTER, wallpaper::CUSTOMIZED, *image.bitmap(),
-      true /*show_wallpaper=*/);
+      WALLPAPER_LAYOUT_CENTER, *image.bitmap(), true /*show_wallpaper=*/);
   RunAllTasksUntilIdle();
   EXPECT_EQ(0, GetWallpaperCount());
   wallpaper::WallpaperInfo wallpaper_info;
@@ -1182,8 +1248,7 @@ TEST_F(WallpaperControllerTest, VerifyWallpaperCache) {
   // Verify |SetCustomWallpaper| updates wallpaper cache for |user1|.
   controller_->SetCustomWallpaper(
       InitializeUser(account_id_1), wallpaper_files_id_1, file_name_1,
-      WALLPAPER_LAYOUT_CENTER, wallpaper::CUSTOMIZED, *image.bitmap(),
-      true /*show_wallpaper=*/);
+      WALLPAPER_LAYOUT_CENTER, *image.bitmap(), true /*show_wallpaper=*/);
   RunAllTasksUntilIdle();
   EXPECT_TRUE(
       controller_->GetWallpaperFromCache(account_id_1, &cached_wallpaper));
@@ -1302,14 +1367,13 @@ TEST_F(WallpaperControllerTest, PreventReloadingSameWallpaper) {
 TEST_F(WallpaperControllerTest, UpdateCustomWallpaperLayout) {
   gfx::ImageSkia image = CreateImage(640, 480, kSmallCustomWallpaperColor);
   WallpaperLayout layout = WALLPAPER_LAYOUT_CENTER;
-  wallpaper::WallpaperType type = wallpaper::CUSTOMIZED;
   SimulateUserLogin(user_1);
 
   // Set a custom wallpaper for the user. Verify that it's set successfully
   // and the wallpaper info is updated.
-  controller_->SetCustomWallpaper(
-      InitializeUser(account_id_1), wallpaper_files_id_1, file_name_1, layout,
-      type, *image.bitmap(), true /*show_wallpaper=*/);
+  controller_->SetCustomWallpaper(InitializeUser(account_id_1),
+                                  wallpaper_files_id_1, file_name_1, layout,
+                                  *image.bitmap(), true /*show_wallpaper=*/);
   RunAllTasksUntilIdle();
   EXPECT_EQ(1, GetWallpaperCount());
   EXPECT_EQ(controller_->GetWallpaperLayout(), layout);
@@ -1318,7 +1382,7 @@ TEST_F(WallpaperControllerTest, UpdateCustomWallpaperLayout) {
                                                 true /* is_persistent */));
   wallpaper::WallpaperInfo expected_wallpaper_info(
       base::FilePath(wallpaper_files_id_1).Append(file_name_1).value(), layout,
-      type, base::Time::Now().LocalMidnight());
+      wallpaper::CUSTOMIZED, base::Time::Now().LocalMidnight());
   EXPECT_EQ(wallpaper_info, expected_wallpaper_info);
 
   // Now change to a different layout. Verify that the layout is updated for

ash/wallpaper/wallpaper_decoder.cc

@@ -6,7 +6,6 @@
 
 #include "ash/shell.h"
 #include "ash/shell_delegate.h"
-#include "base/sequenced_task_runner.h"
 #include "ipc/ipc_channel.h"
 #include "services/data_decoder/public/cpp/decode_image.h"
 
@@ -31,10 +30,14 @@ void ConvertToImageSkia(OnWallpaperDecoded callback, const SkBitmap& image) {
 
 }  // namespace
 
-void DecodeWallpaper(std::unique_ptr<std::string> image_data,
+void DecodeWallpaper(const std::string& image_data,
                      OnWallpaperDecoded callback) {
-  std::vector<uint8_t> image_bytes(image_data.get()->begin(),
-                                   image_data.get()->end());
+  // The connector for the mojo service manager is null in unit tests.
+  if (!Shell::Get()->shell_delegate()->GetShellConnector()) {
+    std::move(callback).Run(gfx::ImageSkia());
+    return;
+  }
+  std::vector<uint8_t> image_bytes(image_data.begin(), image_data.end());
   data_decoder::DecodeImage(
       Shell::Get()->shell_delegate()->GetShellConnector(),
       std::move(image_bytes), data_decoder::mojom::ImageCodec::ROBUST_JPEG,

ash/wallpaper/wallpaper_decoder.h

@@ -20,7 +20,7 @@ using OnWallpaperDecoded =
 
 // Do an async wallpaper decode; |on_decoded| is run on the calling thread when
 // the decode has finished.
-ASH_EXPORT void DecodeWallpaper(std::unique_ptr<std::string> image_data,
+ASH_EXPORT void DecodeWallpaper(const std::string& image_data,
                                 OnWallpaperDecoded callback);
 
 }  // namespace ash

chrome/browser/chromeos/extensions/wallpaper_api.cc

@@ -158,12 +158,12 @@ void WallpaperSetWallpaperFunction::OnWallpaperDecoded(
       extensions::api::wallpaper::ToString(params_->details.layout));
   wallpaper_api_util::RecordCustomWallpaperLayout(layout);
 
-  bool update_wallpaper =
+  bool show_wallpaper =
       account_id_ ==
       user_manager::UserManager::Get()->GetActiveUser()->GetAccountId();
   WallpaperControllerClient::Get()->SetCustomWallpaper(
       account_id_, wallpaper_files_id_, params_->details.filename, layout,
-      wallpaper::CUSTOMIZED, image, update_wallpaper);
+      image, show_wallpaper);
   unsafe_wallpaper_decoder_ = NULL;
 
   // Save current extension name. It will be displayed in the component

chrome/browser/chromeos/extensions/wallpaper_private_api.cc

@@ -513,12 +513,12 @@ void WallpaperPrivateSetCustomWallpaperFunction::OnWallpaperDecoded(
       wallpaper_base::ToString(params->layout));
   wallpaper_api_util::RecordCustomWallpaperLayout(layout);
 
-  bool update_wallpaper =
+  bool show_wallpaper =
       account_id_ ==
       user_manager::UserManager::Get()->GetActiveUser()->GetAccountId();
   WallpaperControllerClient::Get()->SetCustomWallpaper(
-      account_id_, wallpaper_files_id_, params->file_name, layout,
-      wallpaper::CUSTOMIZED, image, update_wallpaper);
+      account_id_, wallpaper_files_id_, params->file_name, layout, image,
+      show_wallpaper);
   unsafe_wallpaper_decoder_ = NULL;
 
   Profile* profile = Profile::FromBrowserContext(browser_context());

chrome/browser/chromeos/login/users/chrome_user_manager_impl.cc

@@ -581,11 +581,9 @@ void ChromeUserManagerImpl::OnExternalDataSet(const std::string& policy,
       user_id, std::string() /* id */, AccountType::UNKNOWN);
   if (policy == policy::key::kUserAvatarImage)
     GetUserImageManager(account_id)->OnExternalDataSet(policy);
-  else if (policy == policy::key::kWallpaperImage)
-    WallpaperManager::Get()->OnPolicySet(policy, account_id);
   else if (policy == policy::key::kNativePrintersBulkConfiguration)
     GetExternalPrinters(account_id)->ClearData();
-  else
+  else if (policy != policy::key::kWallpaperImage)
     NOTREACHED();
 }
 
@@ -595,10 +593,10 @@ void ChromeUserManagerImpl::OnExternalDataCleared(const std::string& policy,
       user_id, std::string() /* id */, AccountType::UNKNOWN);
   if (policy == policy::key::kUserAvatarImage)
     GetUserImageManager(account_id)->OnExternalDataCleared(policy);
-  else if (policy == policy::key::kWallpaperImage)
-    WallpaperManager::Get()->OnPolicyCleared(policy, account_id);
   else if (policy == policy::key::kNativePrintersBulkConfiguration)
     GetExternalPrinters(account_id)->ClearData();
+  else if (policy == policy::key::kWallpaperImage)
+    WallpaperControllerClient::Get()->RemovePolicyWallpaper(account_id);
   else
     NOTREACHED();
 }
@@ -609,16 +607,17 @@ void ChromeUserManagerImpl::OnExternalDataFetched(
     std::unique_ptr<std::string> data) {
   const AccountId account_id = user_manager::known_user::GetAccountId(
       user_id, std::string() /* id */, AccountType::UNKNOWN);
-  if (policy == policy::key::kUserAvatarImage)
+  if (policy == policy::key::kUserAvatarImage) {
     GetUserImageManager(account_id)
         ->OnExternalDataFetched(policy, std::move(data));
-  else if (policy == policy::key::kWallpaperImage)
-    WallpaperManager::Get()->OnPolicyFetched(policy, account_id,
-                                             std::move(data));
-  else if (policy == policy::key::kNativePrintersBulkConfiguration)
+  } else if (policy == policy::key::kNativePrintersBulkConfiguration) {
     GetExternalPrinters(account_id)->SetData(std::move(data));
-  else
+  } else if (policy == policy::key::kWallpaperImage) {
+    WallpaperControllerClient::Get()->SetPolicyWallpaper(account_id,
+                                                         std::move(data));
+  } else {
     NOTREACHED();
+  }
 }
 
 void ChromeUserManagerImpl::OnPolicyUpdated(const std::string& user_id) {

chrome/browser/chromeos/login/users/user_manager_unittest.cc

@@ -24,6 +24,7 @@
 #include "chrome/test/base/testing_browser_process.h"
 #include "chrome/test/base/testing_profile.h"
 #include "chromeos/chromeos_switches.h"
+#include "chromeos/cryptohome/system_salt_getter.h"
 #include "chromeos/dbus/dbus_thread_manager.h"
 #include "chromeos/settings/cros_settings_names.h"
 #include "components/prefs/pref_service.h"
@@ -182,6 +183,11 @@ TEST_F(UserManagerTest, RetrieveTrustedDevicePolicies) {
 }
 
 TEST_F(UserManagerTest, RemoveAllExceptOwnerFromList) {
+  // System salt is needed to remove user wallpaper.
+  SystemSaltGetter::Initialize();
+  SystemSaltGetter::Get()->SetRawSaltForTesting(
+      SystemSaltGetter::RawSalt({1, 2, 3, 4, 5, 6, 7, 8}));
+
   user_manager::UserManager::Get()->UserLoggedIn(
       owner_account_id_at_invalid_domain_,
       owner_account_id_at_invalid_domain_.GetUserEmail(),

chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager.cc

@@ -99,11 +99,6 @@ bool HasNonDeviceLocalAccounts(const user_manager::UserList& users) {
   return false;
 }
 
-// Call |closure| when HashWallpaperFilesIdStr will not assert().
-void CallWhenCanGetFilesId(const base::Closure& closure) {
-  SystemSaltGetter::Get()->AddOnSystemSaltReady(closure);
-}
-
 // A helper to set the wallpaper image for Classic Ash and Mash.
 void SetWallpaper(const gfx::ImageSkia& image, wallpaper::WallpaperInfo info) {
   if (ash_util::IsRunningInMash()) {
@@ -257,19 +252,6 @@ void WallpaperManager::AddObservers() {
                      weak_factory_.GetWeakPtr()));
 }
 
-void WallpaperManager::OnPolicyFetched(const std::string& policy,
-                                       const AccountId& account_id,
-                                       std::unique_ptr<std::string> data) {
-  if (!data)
-    return;
-
-  user_image_loader::StartWithData(
-      task_runner_, std::move(data), ImageDecoder::ROBUST_JPEG_CODEC,
-      0,  // Do not crop.
-      base::Bind(&WallpaperManager::SetPolicyControlledWallpaper,
-                 weak_factory_.GetWeakPtr(), account_id));
-}
-
 bool WallpaperManager::IsPolicyControlled(const AccountId& account_id) const {
   if (!ash::Shell::HasInstance() || ash_util::IsRunningInMash()) {
     // Some unit tests come here without a Shell instance.
@@ -284,28 +266,6 @@ bool WallpaperManager::IsPolicyControlled(const AccountId& account_id) const {
       account_id, is_persistent);
 }
 
-void WallpaperManager::OnPolicySet(const std::string& policy,
-                                   const AccountId& account_id) {
-  WallpaperInfo info;
-  GetUserWallpaperInfo(account_id, &info);
-  info.type = wallpaper::POLICY;
-  SetUserWallpaperInfo(account_id, info, true /*is_persistent=*/);
-}
-
-void WallpaperManager::OnPolicyCleared(const std::string& policy,
-                                       const AccountId& account_id) {
-  WallpaperInfo info;
-  GetUserWallpaperInfo(account_id, &info);
-  info.type = wallpaper::DEFAULT;
-  SetUserWallpaperInfo(account_id, info, true /*is_persistent=*/);
-
-  // If we're at the login screen, do not change the wallpaper but defer it
-  // until the user logs in to the system.
-  if (user_manager::UserManager::Get()->IsUserLoggedIn()) {
-    SetDefaultWallpaperImpl(account_id, true /*show_wallpaper=*/);
-  }
-}
-
 void WallpaperManager::OpenWallpaperPicker() {
   if (wallpaper_manager_util::ShouldUseAndroidWallpapersApp(
           ProfileHelper::Get()->GetProfileByUser(
@@ -465,32 +425,4 @@ void WallpaperManager::SetDefaultWallpaperImpl(const AccountId& account_id,
       account_id, user->GetType(), show_wallpaper);
 }
 
-void WallpaperManager::SetPolicyControlledWallpaper(
-    const AccountId& account_id,
-    std::unique_ptr<user_manager::UserImage> user_image) {
-  if (!WallpaperControllerClient::Get()->CanGetWallpaperFilesId()) {
-    CallWhenCanGetFilesId(
-        base::Bind(&WallpaperManager::SetPolicyControlledWallpaper,
-                   weak_factory_.GetWeakPtr(), account_id,
-                   base::Passed(std::move(user_image))));
-    return;
-  }
-
-  const wallpaper::WallpaperFilesId wallpaper_files_id =
-      WallpaperControllerClient::Get()->GetFilesId(account_id);
-
-  if (!wallpaper_files_id.is_valid())
-    LOG(FATAL) << "Wallpaper flies id if invalid!";
-
-  // If we're at the login screen, do not change the wallpaper to the user
-  // policy controlled wallpaper but only update the cache. It will be later
-  // updated after the user logs in.
-  WallpaperControllerClient::Get()->SetCustomWallpaper(
-      account_id, wallpaper_files_id, "policy-controlled.jpeg",
-      wallpaper::WALLPAPER_LAYOUT_CENTER_CROPPED, wallpaper::POLICY,
-      user_image->image(),
-      user_manager::UserManager::Get()
-          ->IsUserLoggedIn() /* update wallpaper */);
-}
-
 }  // namespace chromeos

chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager.h

@@ -39,10 +39,6 @@ class CommandLine;
 class SequencedTaskRunner;
 }  // namespace base
 
-namespace user_manager {
-class UserImage;
-}  // namespace user_manager
-
 namespace chromeos {
 
 // Asserts that the current task is sequenced with any other task that calls
@@ -96,22 +92,9 @@ class WallpaperManager : public wm::ActivationChangeObserver,
   // Adds |this| as an observer to various settings.
   void AddObservers();
 
-  // Called when the policy-set wallpaper has been fetched.  Initiates decoding
-  // of the JPEG |data| with a callback to SetPolicyControlledWallpaper().
-  void OnPolicyFetched(const std::string& policy,
-                       const AccountId& account_id,
-                       std::unique_ptr<std::string> data);
-
   // A wrapper of |WallpaperController::IsPolicyControlled|.
   bool IsPolicyControlled(const AccountId& account_id) const;
 
-  // Called when a wallpaper policy has been set for |account_id|.  Blocks user
-  // from changing the wallpaper.
-  void OnPolicySet(const std::string& policy, const AccountId& account_id);
-
-  // Called when the wallpaper policy has been cleared for |account_id|.
-  void OnPolicyCleared(const std::string& policy, const AccountId& account_id);
-
   // Opens the wallpaper picker window.
   void OpenWallpaperPicker();
 
@@ -154,12 +137,6 @@ class WallpaperManager : public wm::ActivationChangeObserver,
   void SetDefaultWallpaperImpl(const AccountId& account_id,
                                bool show_wallpaper);
 
-  // Set wallpaper to |user_image| controlled by policy.  (Takes a UserImage
-  // because that's the callback interface provided by UserImageLoader.)
-  void SetPolicyControlledWallpaper(
-      const AccountId& account_id,
-      std::unique_ptr<user_manager::UserImage> user_image);
-
   // Returns the cached logged-in user wallpaper info, or a dummy value under
   // mash.
   wallpaper::WallpaperInfo* GetCachedWallpaperInfo();

chrome/browser/ui/ash/test_wallpaper_controller.cc

@@ -33,7 +33,6 @@ void TestWallpaperController::SetCustomWallpaper(
     const std::string& wallpaper_files_id,
     const std::string& file_name,
     wallpaper::WallpaperLayout layout,
-    wallpaper::WallpaperType type,
     const SkBitmap& image,
     bool show_wallpaper) {
   set_custom_wallpaper_count_++;
@@ -62,6 +61,13 @@ void TestWallpaperController::SetCustomizedDefaultWallpaper(
   NOTIMPLEMENTED();
 }
 
+void TestWallpaperController::SetPolicyWallpaper(
+    ash::mojom::WallpaperUserInfoPtr user_info,
+    const std::string& wallpaper_files_id,
+    const std::string& data) {
+  NOTIMPLEMENTED();
+}
+
 void TestWallpaperController::SetDeviceWallpaperPolicyEnforced(bool enforced) {
   NOTIMPLEMENTED();
 }
@@ -87,6 +93,12 @@ void TestWallpaperController::RemoveUserWallpaper(
   remove_user_wallpaper_count_++;
 }
 
+void TestWallpaperController::RemovePolicyWallpaper(
+    ash::mojom::WallpaperUserInfoPtr user_info,
+    const std::string& wallpaper_files_id) {
+  NOTIMPLEMENTED();
+}
+
 void TestWallpaperController::SetWallpaper(
     const SkBitmap& wallpaper,
     const wallpaper::WallpaperInfo& wallpaper_info) {

chrome/browser/ui/ash/test_wallpaper_controller.h

@@ -41,7 +41,6 @@ class TestWallpaperController : ash::mojom::WallpaperController {
                           const std::string& wallpaper_files_id,
                           const std::string& file_name,
                           wallpaper::WallpaperLayout layout,
-                          wallpaper::WallpaperType type,
                           const SkBitmap& image,
                           bool show_wallpaper) override;
   void SetOnlineWallpaper(ash::mojom::WallpaperUserInfoPtr user_info,
@@ -56,6 +55,9 @@ class TestWallpaperController : ash::mojom::WallpaperController {
       const GURL& wallpaper_url,
       const base::FilePath& file_path,
       const base::FilePath& resized_directory) override;
+  void SetPolicyWallpaper(ash::mojom::WallpaperUserInfoPtr user_info,
+                          const std::string& wallpaper_files_id,
+                          const std::string& data) override;
   void SetDeviceWallpaperPolicyEnforced(bool enforced) override;
   void UpdateCustomWallpaperLayout(ash::mojom::WallpaperUserInfoPtr user_info,
                                    wallpaper::WallpaperLayout layout) override;
@@ -63,6 +65,8 @@ class TestWallpaperController : ash::mojom::WallpaperController {
   void ShowSigninWallpaper() override;
   void RemoveUserWallpaper(ash::mojom::WallpaperUserInfoPtr user_info,
                            const std::string& wallpaper_files_id) override;
+  void RemovePolicyWallpaper(ash::mojom::WallpaperUserInfoPtr user_info,
+                             const std::string& wallpaper_files_id) override;
   void SetWallpaper(const SkBitmap& wallpaper,
                     const wallpaper::WallpaperInfo& wallpaper_info) override;
   void AddObserver(

chrome/browser/ui/ash/wallpaper_controller_client.cc

@@ -84,15 +84,29 @@ wallpaper::WallpaperFilesId HashWallpaperFilesIdStr(
   return wallpaper::WallpaperFilesId::FromString(result);
 }
 
+// Returns true if wallpaper files id can be returned successfully.
+bool CanGetFilesId() {
+  return chromeos::SystemSaltGetter::IsInitialized() &&
+         chromeos::SystemSaltGetter::Get()->GetRawSalt();
+}
+
+// Calls |callback| when system salt is ready. (|CanGetFilesId| returns true.)
+void AddCanGetFilesIdCallback(const base::Closure& callback) {
+  // System salt may not be initialized in tests.
+  if (chromeos::SystemSaltGetter::IsInitialized())
+    chromeos::SystemSaltGetter::Get()->AddOnSystemSaltReady(callback);
+}
+
 }  // namespace
 
 WallpaperControllerClient::WallpaperControllerClient()
-    : policy_handler_(this), binding_(this) {
+    : policy_handler_(this), binding_(this), weak_factory_(this) {
   DCHECK(!g_wallpaper_controller_client_instance);
   g_wallpaper_controller_client_instance = this;
 }
 
 WallpaperControllerClient::~WallpaperControllerClient() {
+  weak_factory_.InvalidateWeakPtrs();
   DCHECK_EQ(this, g_wallpaper_controller_client_instance);
   g_wallpaper_controller_client_instance = nullptr;
 }
@@ -115,28 +129,17 @@ WallpaperControllerClient* WallpaperControllerClient::Get() {
   return g_wallpaper_controller_client_instance;
 }
 
-bool WallpaperControllerClient::CanGetWallpaperFilesId() const {
-  return chromeos::SystemSaltGetter::IsInitialized() &&
-         chromeos::SystemSaltGetter::Get()->GetRawSalt();
-}
-
 wallpaper::WallpaperFilesId WallpaperControllerClient::GetFilesId(
     const AccountId& account_id) const {
-  // System salt might not be ready in tests. Thus we don't have a valid
-  // wallpaper files id here.
-  if (!CanGetWallpaperFilesId())
-    return wallpaper::WallpaperFilesId();
-
+  DCHECK(CanGetFilesId());
   std::string stored_value;
   if (user_manager::known_user::GetStringPref(account_id, kWallpaperFilesId,
                                               &stored_value)) {
     return wallpaper::WallpaperFilesId::FromString(stored_value);
   }
 
-  // Migrated.
-  const std::string& old_id = account_id.GetUserEmail();
   const wallpaper::WallpaperFilesId wallpaper_files_id =
-      HashWallpaperFilesIdStr(old_id);
+      HashWallpaperFilesIdStr(account_id.GetUserEmail());
   user_manager::known_user::SetStringPref(account_id, kWallpaperFilesId,
                                           wallpaper_files_id.id());
   return wallpaper_files_id;
@@ -147,7 +150,6 @@ void WallpaperControllerClient::SetCustomWallpaper(
     const wallpaper::WallpaperFilesId& wallpaper_files_id,
     const std::string& file_name,
     wallpaper::WallpaperLayout layout,
-    wallpaper::WallpaperType type,
     const gfx::ImageSkia& image,
     bool show_wallpaper) {
   ash::mojom::WallpaperUserInfoPtr user_info =
@@ -155,7 +157,7 @@ void WallpaperControllerClient::SetCustomWallpaper(
   if (!user_info)
     return;
   wallpaper_controller_->SetCustomWallpaper(
-      std::move(user_info), wallpaper_files_id.id(), file_name, layout, type,
+      std::move(user_info), wallpaper_files_id.id(), file_name, layout,
       *image.bitmap(), show_wallpaper);
 }
 
@@ -179,6 +181,18 @@ void WallpaperControllerClient::SetDefaultWallpaper(const AccountId& account_id,
       AccountIdToWallpaperUserInfo(account_id);
   if (!user_info)
     return;
+
+  // Postpone setting the wallpaper until we can get files id.
+  if (!CanGetFilesId()) {
+    LOG(WARNING)
+        << "Cannot get wallpaper files id in SetDefaultWallpaper. This "
+           "should never happen under normal circumstances.";
+    AddCanGetFilesIdCallback(
+        base::Bind(&WallpaperControllerClient::SetDefaultWallpaper,
+                   weak_factory_.GetWeakPtr(), account_id, show_wallpaper));
+    return;
+  }
+
   wallpaper_controller_->SetDefaultWallpaper(
       std::move(user_info), GetFilesId(account_id).id(), show_wallpaper);
 }
@@ -191,6 +205,30 @@ void WallpaperControllerClient::SetCustomizedDefaultWallpaper(
                                                        resized_directory);
 }
 
+void WallpaperControllerClient::SetPolicyWallpaper(
+    const AccountId& account_id,
+    std::unique_ptr<std::string> data) {
+  if (!data)
+    return;
+
+  ash::mojom::WallpaperUserInfoPtr user_info =
+      AccountIdToWallpaperUserInfo(account_id);
+  if (!user_info)
+    return;
+
+  // Postpone setting the wallpaper until we can get files id. See
+  // https://crbug.com/615239.
+  if (!CanGetFilesId()) {
+    AddCanGetFilesIdCallback(base::Bind(
+        &WallpaperControllerClient::SetPolicyWallpaper,
+        weak_factory_.GetWeakPtr(), account_id, base::Passed(std::move(data))));
+    return;
+  }
+
+  wallpaper_controller_->SetPolicyWallpaper(std::move(user_info),
+                                            GetFilesId(account_id).id(), *data);
+}
+
 void WallpaperControllerClient::UpdateCustomWallpaperLayout(
     const AccountId& account_id,
     wallpaper::WallpaperLayout layout) {
@@ -220,10 +258,44 @@ void WallpaperControllerClient::RemoveUserWallpaper(
       AccountIdToWallpaperUserInfo(account_id);
   if (!user_info)
     return;
+
+  // Postpone removing the wallpaper until we can get files id.
+  if (!CanGetFilesId()) {
+    LOG(WARNING)
+        << "Cannot get wallpaper files id in RemoveUserWallpaper. This "
+           "should never happen under normal circumstances.";
+    AddCanGetFilesIdCallback(
+        base::Bind(&WallpaperControllerClient::RemoveUserWallpaper,
+                   weak_factory_.GetWeakPtr(), account_id));
+    return;
+  }
+
   wallpaper_controller_->RemoveUserWallpaper(std::move(user_info),
                                              GetFilesId(account_id).id());
 }
 
+void WallpaperControllerClient::RemovePolicyWallpaper(
+    const AccountId& account_id) {
+  ash::mojom::WallpaperUserInfoPtr user_info =
+      AccountIdToWallpaperUserInfo(account_id);
+  if (!user_info)
+    return;
+
+  // Postpone removing the wallpaper until we can get files id.
+  if (!CanGetFilesId()) {
+    LOG(WARNING)
+        << "Cannot get wallpaper files id in RemovePolicyWallpaper. This "
+           "should never happen under normal circumstances.";
+    AddCanGetFilesIdCallback(
+        base::Bind(&WallpaperControllerClient::RemovePolicyWallpaper,
+                   weak_factory_.GetWeakPtr(), account_id));
+    return;
+  }
+
+  wallpaper_controller_->RemovePolicyWallpaper(std::move(user_info),
+                                               GetFilesId(account_id).id());
+}
+
 void WallpaperControllerClient::OpenWallpaperPicker() {
   // TODO(crbug.com/776464): Inline the implementation after WallpaperManager
   // is removed.

chrome/browser/ui/ash/wallpaper_controller_client.h

@@ -32,10 +32,6 @@ class WallpaperControllerClient : public ash::mojom::WallpaperControllerClient,
 
   static WallpaperControllerClient* Get();
 
-  // TODO(crbug.com/776464): Move this to anonymous namesapce.
-  // Returns true if wallpaper files id can be returned successfully.
-  bool CanGetWallpaperFilesId() const;
-
   // Returns files identifier for the |account_id|.
   wallpaper::WallpaperFilesId GetFilesId(const AccountId& account_id) const;
 
@@ -44,7 +40,6 @@ class WallpaperControllerClient : public ash::mojom::WallpaperControllerClient,
                           const wallpaper::WallpaperFilesId& wallpaper_files_id,
                           const std::string& file_name,
                           wallpaper::WallpaperLayout layout,
-                          wallpaper::WallpaperType type,
                           const gfx::ImageSkia& image,
                           bool show_wallpaper);
   void SetOnlineWallpaper(const AccountId& account_id,
@@ -56,11 +51,14 @@ class WallpaperControllerClient : public ash::mojom::WallpaperControllerClient,
   void SetCustomizedDefaultWallpaper(const GURL& wallpaper_url,
                                      const base::FilePath& file_path,
                                      const base::FilePath& resized_directory);
+  void SetPolicyWallpaper(const AccountId& account_id,
+                          std::unique_ptr<std::string> data);
   void UpdateCustomWallpaperLayout(const AccountId& account_id,
                                    wallpaper::WallpaperLayout layout);
   void ShowUserWallpaper(const AccountId& account_id);
   void ShowSigninWallpaper();
   void RemoveUserWallpaper(const AccountId& account_id);
+  void RemovePolicyWallpaper(const AccountId& account_id);
 
   // ash::mojom::WallpaperControllerClient:
   void OpenWallpaperPicker() override;
@@ -84,6 +82,8 @@ class WallpaperControllerClient : public ash::mojom::WallpaperControllerClient,
   // Binds to the client interface.
   mojo::Binding<ash::mojom::WallpaperControllerClient> binding_;
 
+  base::WeakPtrFactory<WallpaperControllerClient> weak_factory_;
+
   DISALLOW_COPY_AND_ASSIGN(WallpaperControllerClient);
 };