Encode path info when redirecting to SPA in exp. mgr.

In the Experience Manager, if a site map item of an SPA channel contains an accented character, clicking it on the left side is not processed correctly.

For example, as visible in the network tab in dev tools, clicking site map item grün:

[site]/[channel]/gr%C3%BCn // UTF-8 encoded

is redirected to

 
[SPA]/gr%FCn // ISO-8859-1 encoded

The redirect takes place in org.hippoecm.hst.container.HstDelegateeFilterBean#doRedirectPreviewURL where the path info is appended to the configured SPA URL, but not URL encoded.

Normally there are no site map items with diacritics because that is prevented while creating content. However, when creating HST landing pages from the Experience Manager, site map items can still be save with diacritics. CMS-12566 exists to close that loophole.