[Mac] Revert to using the public API to display notification icons

chrome/browser/ui/cocoa/notifications/notification_builder_mac.mm

Index: chrome/browser/ui/cocoa/notifications/notification_builder_mac.mm
diff --git a/chrome/browser/ui/cocoa/notifications/notification_builder_mac.mm b/chrome/browser/ui/cocoa/notifications/notification_builder_mac.mm
index 5b3307afd4116ccc5bf41c381c312c5dc34551c2..ab05e04c09f3130c366c1ea22d01270d7166c30a 100644
--- a/chrome/browser/ui/cocoa/notifications/notification_builder_mac.mm
+++ b/chrome/browser/ui/cocoa/notifications/notification_builder_mac.mm
@@ -132,17 +132,15 @@ NSString* const kNotificationSettingsButtonTag = @"settingsButton";
 
   // Icon
   if ([notificationData_ objectForKey:kNotificationImage]) {
-    if ([toast respondsToSelector:@selector(_identityImage)]) {
-      if ([[NSImage class] conformsToProtocol:@protocol(NSSecureCoding)]) {
-        NSImage* image = [notificationData_ objectForKey:kNotificationImage];
-        [toast setValue:image forKey:@"_identityImage"];
-      } else {  // NSImage only conforms to NSSecureCoding from 10.10 onwards.
-        base::scoped_nsobject<NSImage> image([[NSImage alloc]
-            initWithData:[notificationData_ objectForKey:kNotificationImage]]);
-        [toast setValue:image forKey:@"_identityImage"];
-      }
-      [toast setValue:@NO forKey:@"_identityImageHasBorder"];
+    if ([[NSImage class] conformsToProtocol:@protocol(NSSecureCoding)]) {
+      NSImage* image = [notificationData_ objectForKey:kNotificationImage];
+      [toast setValue:image forKey:@"contentImage"];
+    } else {  // NSImage only conforms to NSSecureCoding from 10.10 onwards.
+      base::scoped_nsobject<NSImage> image([[NSImage alloc]
+          initWithData:[notificationData_ objectForKey:kNotificationImage]]);
+      [toast setValue:image forKey:@"contentImage"];
     }
+    [toast setValue:@NO forKey:@"_identityImageHasBorder"];

[Robert Sesek, 2017/03/22 14:36:16]

Is this still necessary?

   }
 
   // Buttons