Return attachment id in api response to attachment upload (#23566).

Patch by Jan Schulz-Hofen.

git-svn-id: http://svn.redmine.org/redmine/trunk@15762 e93f8b46-1217-0410-a6f0-8f06a7374b81

app/views/attachments/upload.api.rsb

@@ -1,3 +1,4 @@
 api.upload do
+  api.id    @attachment.id
   api.token @attachment.token
 end

test/integration/api_test/attachments_test.rb

@@ -111,9 +111,12 @@ class Redmine::ApiTest::AttachmentsTest < Redmine::ApiTest::Base
     assert_kind_of Hash, xml['upload']
     token = xml['upload']['token']
     assert_not_nil token
+    attachment_id = xml['upload']['id']
+    assert_not_nil attachment_id
 
     attachment = Attachment.order('id DESC').first
     assert_equal token, attachment.token
+    assert_equal attachment_id, attachment.id.to_s
     assert_nil attachment.container
     assert_equal 2, attachment.author_id
     assert_equal 'File content'.size, attachment.filesize