Apply the file preview shadow frame to most previews instead of only image file previews
Review Request #129918 - Created Feb. 4, 2017 and submitted
This is basically the same patch as https://git.reviewboard.kde.org/r/118961/ which I discarded as the diff was blank and updating it didn't work (probably because it was old pre-Qt/Frameworks 5 ?).
Anyways, currently image file previews have a nice shadow around the thumbnail.
It looks nice and modern but the same shadow doesn't get applied to anything else such as video previews.
This makes non-image previews look out of place (especially in mixed content folders) and, IMHO, ugly. Especially with the new modern look Plasma 5 brought.
The patch applies the shadow to all previews except for folders, fonts and Win32 exe/dll previews, similar to how Windows and MacOS handles it.
Enabled all previews and created a folder with common file types (see screenshots) - works as intended.
Note that most of the thumbnail generators inside kio-extras/thumbnail currently add a 1px black and white border directly into the cached thumbnail image to give them a 3d-depth look.
This causes the border of the preview to look slightly blurry/unsharp with the shadow around it (see the text previews in the screenshots).
The fix for this is a simple patch to make thier flags() function return ThumbCreator::None instead of ThumbCreator::DrawFrame.
Edit: fix https://git.reviewboard.kde.org/r/129921/