Currently, ImageViewer always uses nearest neighbor scaling.
This allows the user to choose whether to use nearest neighbor
or bilinear scaling. It current defaults to nearest neighbor.
Before there was dialogs to indicate if
current file is last or first.
So in this commit, I added functionality to enable
and disable forward and backward navigation based
on if the next file is avialable or not and if the
pervious file is avialable or not, respectively.
ImageViewer: Refactor code and init data
Data intialization was not happening properly, now I did
Initializations properly so that navigation can work from
the very first image.
ImageViewer used two different logic to resize the display window, which
leads to confusing behaviour for rotate function. Now all the resizing
behaviour goes through the existing resize_window function.
Previously some actions like Rotate/Flip/Set as Desktop Wallpaper would
make the application crash if no image was loaded. Now image actions are
enabled/disabled based on whether an image has been loaded or not.
Instead of parsing untrusted and potentially malicious image files in
the ImageViewer GUI process, take advantage of the ImageDecoder service
that we already have on the system to sandbox the decode.
This prevents bugs in our image decoding libraries from being used as
an exploitation vector when viewing files in ImageViewer.
