Revert "Fix multi layer movement in tilemap mode (fix aseprite#3144)"

This reverts commit bc050e8.

Merge branch 'main' into beta

Fix multi layer movement in tilemap mode (fix aseprite#3144)

Before this fix, a multi-layer mask move (with mixed layer types:
normal layer and tilemap layers with different grids) caused loss of
drawing areas.

The heart of this solution is to correctly align the 'selection mask'
and 'transform data' according to the layer's grid, and also, forcing
'site' TilemapMode/TilesetMode before each
reproduceAllTransformationsWithInnerCmds() iteration.

The scale transformation could have some things to improve in later
commits. Not fully tested yet.

Fix crash when showing the palette popup (fix aseprite#3189)

Fix forward declaration of os::Sampling

Merge branch 'main' into beta

Fix "Reset Scale" notification when there is enough workarea available

Instead of using the window size, we can use the available workarea to
know that the user can resize the main window to its full size and
there will be enough room to display some common dialogs like the
Preferences one.

Show selected index correctly in PaletteViews used from ColorPopups (…

…regression introduced in d164458)

Merge branch 'main' into beta

Fix crash using Shift key in Pencil tool

Bug introduced in f3fd0de