Support alerts on macOS 10.15.3+ again

The latest beta of 10.15.3 fixed the issue where an XPC service could
not show notifications. This removes the workaround we put in place in
https://crrev.com/c/1883648 for macOS 10.15.3+ but keeps it for earlier
versions of 10.15.

Bug: 1007418
Change-Id: I928dac7366c9e7faee793dd72d282b031e535092
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1991637
Commit-Queue: Richard Knoll <knollr@chromium.org>
Reviewed-by: Robert Sesek <rsesek@chromium.org>
Cr-Commit-Position: refs/heads/master@{#730122}

chrome/browser/notifications/notification_platform_bridge_mac.h

@@ -53,6 +53,9 @@ class NotificationPlatformBridgeMac : public NotificationPlatformBridge {
   // when a notification gets activated.
   static bool VerifyNotificationData(NSDictionary* response) WARN_UNUSED_RESULT;
 
+  // Returns if alerts are supported on this machine.
+  static bool SupportsAlerts();
+
  private:
   // Cocoa class that receives callbacks from the NSUserNotificationCenter.
   base::scoped_nsobject<NotificationCenterDelegate> delegate_;

chrome/browser/notifications/notification_platform_bridge_mac.mm

@@ -23,6 +23,7 @@
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/sys_string_conversions.h"
 #include "base/strings/utf_string_conversions.h"
+#include "base/system/sys_info.h"
 #include "base/task/post_task.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/notifications/notification_common.h"
@@ -123,10 +124,7 @@ base::string16 CreateNotificationTitle(
 
 bool IsPersistentNotification(
     const message_center::Notification& notification) {
-  // TODO(crbug.com/1007418): Remove this and find a way to show alert style
-  // notifications in 10.15 and above. At least show them as banners until then
-  // as a temporary workaround.
-  if (base::mac::IsAtLeastOS10_15())
+  if (!NotificationPlatformBridgeMac::SupportsAlerts())
     return false;
 
   return notification.never_timeout() ||
@@ -174,6 +172,19 @@ base::string16 CreateNotificationContext(
 
   return etldplusone;
 }
+
+// Implements the version check to determine if alerts are supported. Do not
+// call this method directly as SysInfo::OperatingSystemVersionNumbers might be
+// an expensive call. Instead use NotificationPlatformBridgeMac::SupportsAlerts
+// which caches this value.
+bool SupportsAlertsImpl() {
+  int32_t major, minor, bugfix;
+  base::SysInfo::OperatingSystemVersionNumbers(&major, &minor, &bugfix);
+  // Allow alerts on all versions except 10.15.0, 10.15.1 & 10.15.2.
+  // See crbug.com/1007418 for details.
+  return major != 10 || minor != 15 || bugfix > 2;
+}
+
 }  // namespace
 
 // A Cocoa class that represents the delegate of NSUserNotificationCenter and
@@ -462,6 +473,13 @@ bool NotificationPlatformBridgeMac::VerifyNotificationData(
   return true;
 }
 
+// static
+bool NotificationPlatformBridgeMac::SupportsAlerts() {
+  // Cache result as SysInfo::OperatingSystemVersionNumbers might be expensive.
+  static bool supports_alerts = SupportsAlertsImpl();
+  return supports_alerts;
+}
+
 // /////////////////////////////////////////////////////////////////////////////
 @implementation NotificationCenterDelegate
 - (void)userNotificationCenter:(NSUserNotificationCenter*)center

chrome/browser/notifications/notification_platform_bridge_mac_unittest.mm

@@ -281,8 +281,7 @@ TEST_F(NotificationPlatformBridgeMacTest, TestDisplayOneButton) {
 }
 
 TEST_F(NotificationPlatformBridgeMacTest, TestDisplayProgress) {
-  // TODO(crbug.com/1007418): Enable this when we support alerts on 10.15 again.
-  if (base::mac::IsAtLeastOS10_15())
+  if (!NotificationPlatformBridgeMac::SupportsAlerts())
     return;
 
   std::unique_ptr<Notification> notification =
@@ -362,8 +361,7 @@ TEST_F(NotificationPlatformBridgeMacTest, TestQuitRemovesNotifications) {
 }
 
 TEST_F(NotificationPlatformBridgeMacTest, TestDisplayAlert) {
-  // TODO(crbug.com/1007418): Enable this when we support alerts on 10.15 again.
-  if (base::mac::IsAtLeastOS10_15())
+  if (!NotificationPlatformBridgeMac::SupportsAlerts())
     return;
 
   std::unique_ptr<Notification> alert =
@@ -378,8 +376,7 @@ TEST_F(NotificationPlatformBridgeMacTest, TestDisplayAlert) {
 }
 
 TEST_F(NotificationPlatformBridgeMacTest, TestDisplayBannerAndAlert) {
-  // TODO(crbug.com/1007418): Enable this when we support alerts on 10.15 again.
-  if (base::mac::IsAtLeastOS10_15())
+  if (!NotificationPlatformBridgeMac::SupportsAlerts())
     return;
 
   std::unique_ptr<Notification> alert =
@@ -398,8 +395,7 @@ TEST_F(NotificationPlatformBridgeMacTest, TestDisplayBannerAndAlert) {
 }
 
 TEST_F(NotificationPlatformBridgeMacTest, TestCloseAlert) {
-  // TODO(crbug.com/1007418): Enable this when we support alerts on 10.15 again.
-  if (base::mac::IsAtLeastOS10_15())
+  if (!NotificationPlatformBridgeMac::SupportsAlerts())
     return;
 
   std::unique_ptr<Notification> alert =
@@ -417,8 +413,7 @@ TEST_F(NotificationPlatformBridgeMacTest, TestCloseAlert) {
 }
 
 TEST_F(NotificationPlatformBridgeMacTest, TestQuitRemovesBannersAndAlerts) {
-  // TODO(crbug.com/1007418): Enable this when we support alerts on 10.15 again.
-  if (base::mac::IsAtLeastOS10_15())
+  if (!NotificationPlatformBridgeMac::SupportsAlerts())
     return;
 
   std::unique_ptr<Notification> notification = CreateBanner(