This patch implements the functionality to cancel Drag and Drop
by using the escape key or more general, the ui_cancel action.
Since this would be the third location, where the finalization of
Drag and Drop would have to be implemented, that functionality was
put into the private function _perform_drop.
Simplified gui.drag_data.get_type() != Variant::NIL to gui.dragging
because they are equivalent.
A SubViewport with default-size doesn't display its content, but shows
pink color, until it is resized.
This patch makes sure, that the size gets set during initialization.
When resizing a non-focused window, the previously focused
Window got resized.
This patch grabs focus for the actually resized window, before
starting with the resizing.
When the mouse cursor is over a embedded Window, the Viewport's
last_mouse_position did not get updated.
This patch makes sure that the update happens on every InputEventMouse.
Document canvas layer of embedded Windows.
Affects a lot of classes. Very thoroughly checked signal connections and deferred calls to this method, add_do_method/add_undo_method calls, and so on.
Also renames the internal `_update_callback()` to `_redraw_callback()` for consistency.
Just a few comments have also been changed to say "redraw".
In CPUParticles2D, there was a private variable with the same name. It has been renamed to `do_redraw`.
Mipmap LOD bias can be useful to improve the appearance of distant
textures without increasing anisotropic filtering (or in situations
where anisotropic filtering is not effective).
`fsr_mipmap_bias` was renamed to `texture_mipmap_bias` accordingly.
The property hint now allows for greater precision as well.
`rendering/quality/shadows` is now `rendering/quality/positional_shadow`
to explicitly denote that the settings only affect positional light shadows,
not directional light shadows.
Shadow atlas settings now contain the word "atlas" for easier searching.
Soft shadow quality settings were renamed to contain the word "filter".
This makes the settings appear when searching for "filter" in the
project settings dialog, like in Godot 3.x.
