Base+Userland: Add menu item icons
This adds missing icons to Presenter Presentation menu.
This adds missing icon to Image Viewer View menu.
This adds a scale icon for the Image Viewer and Font Editor.
This moves the Fit Image to View icon to the 16x16 folder as it's now
used by Image Viewer and not only Pixel Paint.
This improves the fullscreen and play icons so that they fit together
better.
We have a new, improved string type coming up in AK (OOM aware, no null
state), and while it's going to use UTF-8, the name UTF8String is a
mouthful - so let's free up the String name by renaming the existing
class.
Making the old one have an annoying name will hopefully also help with
quick adoption :^)
This adds menu item icons for Add Mask, Flatten Image, Fit Image To
View, and Generic 5x5 Convolution.
This modifies the menu item icon for Swap Colors to make the action more
obvious and improve accessibility.
Each of these strings would previously rely on StringView's char const*
constructor overload, which would call __builtin_strlen on the string.
Since we now have operator ""sv, we can replace these with much simpler
versions. This opens the door to being able to remove
StringView(char const*).
No functional changes.
