DLP: Show toast when printing is blocked.

Shows a toast when scripted printing is blocked due to
Data Leak Prevention configuration.

Bug: 1124651
Change-Id: I0cfd0c81fff0ca924a212ab988de3bc869bc53f4
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2421515
Commit-Queue: Sergey Poromov <poromov@chromium.org>
Reviewed-by: Aya Elsayed <ayaelattar@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>
Reviewed-by: Nikita Podguzov <nikitapodguzov@chromium.org>
Cr-Commit-Position: refs/heads/master@{#810506}

chrome/browser/chromeos/BUILD.gn

@@ -2076,6 +2076,8 @@ source_set("chromeos") {
     "policy/dlp/dlp_content_restriction_set.h",
     "policy/dlp/dlp_content_tab_helper.cc",
     "policy/dlp/dlp_content_tab_helper.h",
+    "policy/dlp/dlp_notification_helper.cc",
+    "policy/dlp/dlp_notification_helper.h",
     "policy/dlp/dlp_rules_manager.cc",
     "policy/dlp/dlp_rules_manager.h",
     "policy/dlp/enterprise_clipboard_dlp_controller.cc",

chrome/browser/chromeos/policy/dlp/dlp_notification_helper.cc

+// 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/chromeos/policy/dlp/dlp_notification_helper.h"
+
+#include "ash/public/cpp/toast_data.h"
+#include "ash/public/cpp/toast_manager.h"
+#include "base/optional.h"
+#include "components/strings/grit/components_strings.h"
+#include "ui/base/l10n/l10n_util.h"
+
+namespace policy {
+
+namespace {
+
+const char kPrintToastId[] = "print_dlp_blocked";
+constexpr int kPrintToastDurationMs = 2500;
+
+}  // namespace
+
+void ShowDlpPrintDisabledToast() {
+  ash::ToastData toast(
+      kPrintToastId, l10n_util::GetStringUTF16(IDS_POLICY_DLP_PRINTING_BLOCKED),
+      kPrintToastDurationMs, base::nullopt);
+
+  ash::ToastManager::Get()->Show(toast);
+}
+
+}  // namespace policy

chrome/browser/chromeos/policy/dlp/dlp_notification_helper.h

+// 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 CHROME_BROWSER_CHROMEOS_POLICY_DLP_DLP_NOTIFICATION_HELPER_H_
+#define CHROME_BROWSER_CHROMEOS_POLICY_DLP_DLP_NOTIFICATION_HELPER_H_
+
+namespace policy {
+
+// Shows a notification that printing is not allowed due to DLP rules.
+void ShowDlpPrintDisabledToast();
+
+}  // namespace policy
+
+#endif  // CHROME_BROWSER_CHROMEOS_POLICY_DLP_DLP_NOTIFICATION_HELPER_H_

chrome/browser/printing/print_view_manager.cc

@@ -30,6 +30,7 @@
 
 #if defined(OS_CHROMEOS)
 #include "chrome/browser/chromeos/policy/dlp/dlp_content_manager.h"
+#include "chrome/browser/chromeos/policy/dlp/dlp_notification_helper.h"
 #endif
 
 using content::BrowserThread;
@@ -186,6 +187,9 @@ bool PrintViewManager::RejectPrintPreviewRequestIfRestricted(
   if (!IsPrintingRestricted())
     return false;
   GetPrintRenderFrame(rfh)->OnPrintPreviewDialogClosed();
+#if defined(OS_CHROMEOS)
+  policy::ShowDlpPrintDisabledToast();
+#endif
   return true;
 }
 
@@ -219,8 +223,12 @@ bool PrintViewManager::PrintPreview(
   if (IsCrashed())
     return false;
 
-  if (IsPrintingRestricted())
+  if (IsPrintingRestricted()) {
+#if defined(OS_CHROMEOS)
+    policy::ShowDlpPrintDisabledToast();
+#endif
     return false;
+  }
 
   GetPrintRenderFrame(rfh)->InitiatePrintPreview(std::move(print_renderer),
                                                  has_selection);

components/policy_strings.grdp

@@ -569,7 +569,7 @@ Additional details:
     This application has been blocked by your administrator
   </message>
 
-  <!-- Strings for Data Leak Prevetion -->
+  <!-- Strings for Data Leak Prevention -->
   <message name="IDS_POLICY_DLP_CLIPBOARD_BLOCKED_ON_PASTE" desc="A toast informing the user that paste is blocked.">
     Pasting to this location is blocked by your administrator
   </message>
@@ -579,5 +579,8 @@ Additional details:
   <message name="IDS_POLICY_DLP_CLIPBOARD_BLOCKED_ON_COPY_TWO_VMS" desc="A toast informing the user that sharing clipboard data to VMs is blocked.">
     Your administrator has blocked sharing this content to <ph name="VM_NAME_1">$1<ex>Linux</ex></ph> and <ph name="VM_NAME_2">$2<ex>Parallels</ex></ph>
   </message>
+  <message name="IDS_POLICY_DLP_PRINTING_BLOCKED" desc="A toast informing the user that printing is blocked.">
+    Printing of this content is blocked by your administrator
+  </message>
 
 </grit-part>

components/policy_strings_grdp/IDS_POLICY_DLP_PRINTING_BLOCKED.png.sha1

+e36454c13cd9e034b5a9b21abffdfa0e369a8632
\ No newline at end of file