ui/app: remove IsAlive

IsAlive races with the StageDead event: if the client checks IsAlive
after the stage is updated to StageDead but before having received
the StageDead it will exit the event loop, blocking the StageDead
to ever arrive.

Remove IsAlive and let the client rely only on the StageDead to exit
its event loop.

Signed-off-by: Elias Naur <mail@eliasnaur.com>

ui/app/window.go

@@ -79,14 +79,17 @@ func (w *Window) Timings() string {
 }
 
 func (w *Window) SetTextInput(s key.TextInputState) {
-	if !w.IsAlive() {
+	w.mu.Lock()
+	defer w.mu.Unlock()
+	if !w.isAlive() {
 		return
 	}
 	if s != w.inputState && (s == key.TextInputClose || s == key.TextInputOpen) {
 		w.driver.setTextInput(s)
 	}
 	if s == key.TextInputFocus {
-		w.Redraw()
+		w.setNextFrame(time.Time{})
+		w.updateAnimation()
 	}
 	w.inputState = s
 }
@@ -221,12 +224,6 @@ func (w *Window) Stage() Stage {
 	return w.stage
 }
 
-func (w *Window) IsAlive() bool {
-	w.mu.Lock()
-	defer w.mu.Unlock()
-	return w.isAlive()
-}
-
 func (w *Window) isAlive() bool {
 	return w.stage > StageDead && w.err == nil
 }