To reproduce:
1 Create a database activity including text area fields.
2 Create a new entry including images in the text area
3 Update the entry via the Mobile app

How to fix this:

• The files in the editor are part of the get_entries WS response
• We need to download them and re-upload them upon every edition (like we currently do for assignment)
• So when a user is going to save the updates in the app we have to upload all the editor files via webservice/upload.php to get a draftid that will be used as a parameter of the Web SErvice, example parameters (this is for web, for mobile we have to use the WS signature parameters):

[d] => 2
[rid] => 1
[field_4_0] => https://moodle.org
[field_5_itemid] => 965532203 <-- this is the draft item id used
[field_5] => <p>The Open Source LMS of the world.</p><p><br></p><p><img src="http://localhost/m/stable_master/draftfile.php/5/user/draft/965532203/LOGO.png" alt="" class="img-responsive atto_image_button_text-bottom" width="440" height="168"><br></p>
[field_5_content1] => 1

Data sent by the mobile app right now:

entryid: 1
data[0][fieldid]: 4
data[0][value]: "https://moodle.org"
data[0][subfield]:
data[1][fieldid]: 5
data[1][value]: "<p>The Open Source LMS of the world</p><p>blah blah</p><p><img src=\"@@PLUGINFILE@@/LOGO.png\" alt=\"\" class=\"img-responsive atto_image_button_text-bottom\" width=\"440\" height=\"168\"><br></p>"
data[1][subfield]:
data[2][fieldid]: 5
data[2][subfield]: content1
data[2][value]: 1
data[3][fieldid]: 5
data[3][subfield]: itemid
data[3][value]: 437022570