screenshot-window-sizer: Fix cycling through all valid sizes

When cycling through window sizes, we should skip any sizes that are
bigger than the available area. We do that, but the current code
assumes that the possible sizes are sorted, which is no longer the
case since the addition of "phone" sizes in commit 5b43d4733c.

As a result, we may now skip sizes that would fit perfectly fine.
Address this by filtering out invalid sizes beforehand instead of
assuming a certain order (wich no longer work due to the addition
of a portrait format).

https://gitlab.gnome.org/GNOME/gnome-shell-extensions/merge_requests/97

extensions/screenshot-window-sizer/extension.js

@@ -82,7 +82,8 @@ function cycleScreenshotSizes(display, window, binding) {
 
     // Double both axes if on a hidpi display
     let scaleFactor = St.ThemeContext.get_for_stage(global.stage).scale_factor;
-    let scaledSizes = SIZES.map(size => size.map(wh => wh * scaleFactor));
+    let scaledSizes = SIZES.map(size => size.map(wh => wh * scaleFactor))
+        .filter(([w, h]) => w <= workArea.width && h <= workArea.height);
 
     // Find the nearest 16:9 size for the current window size
     let nearestIndex;
@@ -105,10 +106,7 @@ function cycleScreenshotSizes(display, window, binding) {
 
     // get the next size up or down from ideal
     let newIndex = (nearestIndex + (backwards ? -1 : 1)) % scaledSizes.length;
-    let newWidth, newHeight;
-    [newWidth, newHeight] = scaledSizes[newIndex];
-    if (newWidth > workArea.width || newHeight > workArea.height)
-        [newWidth, newHeight] = scaledSizes[0];
+    let [newWidth, newHeight] = scaledSizes[newIndex];
 
     // Push the window onscreen if it would be resized offscreen
     let newX = outerRect.x;