libview: Check END state when we set PpsViewPresentation to NORMAL
The callback handler of key press event will simply call set_normal if the key pressed is not specially handled. When the state is already END, this will make Key_Left trigger a set_normal (in the key pressed callback) and then call previous_page (in the action handler). The previous_page function won't work as expected since the state is inconsistent.
Fixes #123 (closed)
Signed-off-by: Qiu Wenbo qiuwenbo@gnome.org