Add "Floating Window Mode"

A simple borderless window floating on desktop. Window can be resized and moved by dragging. It also has some minimalistic controls showing on top of the video when cursor is hovering over it.\n\n This was a feature originally requested by @zahid1905.

clapper_src/buttons.js

@@ -17,7 +17,11 @@ class ClapperCustomButton extends Gtk.Button
 
         super._init(opts);
 
+        this.floatUnaffected = false;
+        this.wantedVisible = true;
         this.isFullscreen = false;
+        this.isFloating = false;
+
         this.add_css_class('flat');
     }
 
@@ -30,6 +34,32 @@ class ClapperCustomButton extends Gtk.Button
         this.isFullscreen = isFullscreen;
     }
 
+    setFloatingMode(isFloating)
+    {
+        if(this.isFloating === isFloating)
+            return;
+
+        this.isFloating = isFloating;
+
+        if(this.floatUnaffected)
+            return;
+
+        if(isFloating)
+            super.set_visible(false);
+        else
+            super.set_visible(this.wantedVisible);
+    }
+
+    set_visible(isVisible)
+    {
+        this.wantedVisible = isVisible;
+
+        if(this.isFloating && !this.floatUnaffected)
+            super.set_visible(false);
+        else
+            super.set_visible(isVisible);
+    }
+
     vfunc_clicked()
     {
         if(!this.isFullscreen)
@@ -48,6 +78,14 @@ class ClapperIconButton extends CustomButton
         super._init({
             icon_name: icon,
         });
+        this.floatUnaffected = true;
+    }
+
+    setFullscreenMode(isFullscreen)
+    {
+        /* Redraw icon after style class change */
+        this.set_icon_name(this.icon_name);
+        super.setFullscreenMode(isFullscreen);
     }
 });
 
@@ -87,7 +125,6 @@ class ClapperLabelButton extends CustomButton
             label: text,
             single_line_mode: true,
         });
-
         this.customLabel.add_css_class('labelbutton');
         this.set_child(this.customLabel);
     }
@@ -105,6 +142,7 @@ class ClapperPopoverButton extends IconButton
     {
         super._init(icon);
 
+        this.floatUnaffected = false;
         this.popover = new Gtk.Popover({
             position: Gtk.PositionType.TOP,
         });
@@ -131,7 +169,7 @@ class ClapperPopoverButton extends IconButton
         this.popover.set_offset(0, -this.margin_top);
 
         let cssClass = 'osd';
-        if(isFullscreen == this.popover.has_css_class(cssClass))
+        if(isFullscreen === this.popover.has_css_class(cssClass))
             return;
 
         let action = (isFullscreen) ? 'add' : 'remove';