Office Importer images URL encoding

When uploading office documents with special characters in, any images inside the document fail to embed in the wiki page correctly. They upload fine, but they do not embed into the page.

Steps to Reproduce

1. Create a word document and insert an image
2. Call the word document test+test.docx. It is the plus in the file name that will cause an issue here.
3. Create a new page from office
4. Select this document. Leave filter styles checked and split document unchecked. Click import
5. You will see the image has attached correctly, but is not embedded in the page.

This is due to a url encoding issue. If you browse to the attachment by clicking the link in the attachment list, the URL is

/test%2Btest_html_fe01401db7965b06.png

However, the image embeded in the page is

/test test_html_fe01401db7965b06.png?width=602&height=241

Note the embedded image has replaced the %2B with a space incorrectly.