Merged r17150 to 3.3-stable (#26699).

git-svn-id: http://svn.redmine.org/redmine/branches/3.3-stable@17152 e93f8b46-1217-0410-a6f0-8f06a7374b81

app/helpers/application_helper.rb

@@ -1278,7 +1278,13 @@ module ApplicationHelper
       elsif user.to_s =~ %r{<(.+?)>}
         email = $1
       end
-      return gravatar(email.to_s.downcase, options) unless email.blank? rescue nil
+      if email.present?
+        gravatar(email.to_s.downcase, options) rescue nil
+      else
+        image_tag 'anonymous.png',
+                  GravatarHelper::DEFAULT_OPTIONS
+                    .except(:default, :rating, :ssl).merge(options)
+      end
     else
       ''
     end