ScreenManager: reduce ScreenManager_resize

The main change is the header hight being not included in y1.
This is important if a sub-manager gets resized, e.g. a resize while
editing the Settings or in a pickFromVector selection, and afterwards,
then the sub-manager is closed, the super-ScreenManager gets resized, it
uses the correct header hight.
The header hight might have been changed since the last resize of the
super-manager in the Settings by adding/removing some meters.

This fixes new meters being hidden after added at runtime after a resize
in the main window.

AvailableMetersPanel.c

@@ -81,7 +81,7 @@ static HandlerResult AvailableMetersPanel_eventHandler(Panel* super, int ch) {
       Header_calculateHeight(header);
       Header_updateData(header);
       Header_draw(header);
-      ScreenManager_resize(this->scr, this->scr->x1, header->height, this->scr->x2, this->scr->y2);
+      ScreenManager_resize(this->scr);
    }
    return result;
 }