Emoticons with dashes are not correctly restored in 6.15.5

Issue Summary

Environment

Confluence 6.15.5, pages saved in earlier versions of Confluence with broken emoticons ("broken" as per https://jira.atlassian.com/browse/CONFSERVER-52441)

Steps to Reproduce

1. Have a page with a "broken" emoticon (saved in storage format as an "<img>") which has a dash in the name (e.g. "thumbs-up", "thumbs-down", "green-star", "red-star", "yellow-star", "blue-star", "light-off", "light-on", "broken-heart")
2. Upgrade to 6.15.5

Expected Results

The emoticons are restored, can be viewed correctly on the view page and are correctly saved on next save. 

Actual Results

The emoticons are incorrectly converted to HipChat emoticons (which are "unknown").

Workaround

Disable the "Confluence HipChat Emoticons Plugin"

1. Go to   > Manage apps
2. Search for Confluence Hipchat Emoticons Plugin. This is a bundled plugin, so make sure the All apps option is selected in dropdown.
3. Click on the name of the plugin, then select Disable.

Alternatively, the fixed version of the  "Confluence HipChat Emoticons Plugin" can be installed in your 6.15.5 instance

1. Go to   > Manage apps
2. Press "Upload app"
3. Upload the fixed version of the plugin attached to this ticket confluence-hipchat-emoticons-plugin-3.1.3.obr