check for having global permission to export_issues if no project is provided

* optimizing project retreival

app/controllers/issues_controller.rb

@@ -14,7 +14,7 @@
 
 class IssuesController < ApplicationController
   EXPORT_FORMATS = %w[atom rss api xls csv pdf]
-  
+
   menu_item :new_issue, :only => [:new, :create]
   menu_item :view_all_issues, :only => [:all]
   default_search_scope :issues
@@ -24,8 +24,8 @@ class IssuesController < ApplicationController
   before_filter :check_project_uniqueness, :only => [:move, :perform_move]
   before_filter :find_project, :only => [:new, :create]
   before_filter :authorize, :except => [:index, :all]
-  before_filter :protect_from_unauthorized_export, :only => [:index, :all]
   before_filter :find_optional_project, :only => [:index, :all]
+  before_filter :protect_from_unauthorized_export, :only => [:index, :all]
   before_filter :check_for_default_issue_status, :only => [:new, :create]
   before_filter :build_new_issue_from_params, :only => [:new, :create]
   before_filter :retrieve_query, :only => [:index, :all]
@@ -323,12 +323,12 @@ private
     attributes[:custom_field_values].reject! {|k,v| v.blank?} if attributes[:custom_field_values]
     attributes
   end
-  
+
   def protect_from_unauthorized_export
     return true unless EXPORT_FORMATS.include? params[:format]
-    
-    find_optional_project
-    return true if User.current.allowed_to? :export_issues, @project
+
+    find_optional_project if @project.nil?
+    return true if User.current.allowed_to? :export_issues, @project, :global => @project.nil?
 
     # otherwise deny access
     params[:format] = 'html'