Remove references to MainWindow

backend.go

@@ -17,13 +17,13 @@ type Backend interface {
 	NewSurfaceBox   () (SurfaceBox, error)
 	NewContainerBox () ContainerBox
 
-	// NewWindow creates a normal MainWindow and returns it.
-	NewWindow (image.Rectangle) (MainWindow, error)
+	// NewWindow creates a normal Window and returns it.
+	NewWindow (image.Rectangle) (Window, error)
 
 	// NewPlainWindow creates an undecorated window that does not appear in
 	// window lists and returns it. This is intended for making things like
 	// panels, docks, etc.
-	NewPlainWindow (image.Rectangle) (MainWindow, error)
+	NewPlainWindow (image.Rectangle) (Window, error)
 
 	// NewTexture creates a new texture from an image. The backend must
 	// reject any texture that was not made by it.

tomo.go

@@ -50,7 +50,7 @@ func Do (callback func ()) {
 }
 
 // NewWindow creates and returns a window within the specified bounds on screen.
-func NewWindow (bounds image.Rectangle) (MainWindow, error) {
+func NewWindow (bounds image.Rectangle) (Window, error) {
 	assertBackend()
 	return backend.NewWindow(bounds)
 }
@@ -58,7 +58,7 @@ func NewWindow (bounds image.Rectangle) (MainWindow, error) {
 // NewPlainWindow is like NewWindow, but it creates an undecorated window that
 // does not appear in window lists. It is intended for creating things like
 // docks, panels, etc.
-func NewPlainWindow (bounds image.Rectangle) (MainWindow, error) {
+func NewPlainWindow (bounds image.Rectangle) (Window, error) {
 	assertBackend()
 	return backend.NewPlainWindow(bounds)
 }