Use setMinimized() during window initialization

If setMinimized() is used during window initialization, no animation
will be played, so we could use setMinimized() instead of minimize()
that takes "avoid animation" boolean trap.

src/x11window.cpp

@@ -859,9 +859,7 @@ bool X11Window::manage(xcb_window_t w, bool isMapped)
         }
     }
 
-    if (init_minimize) {
-        minimize(true); // No animation
-    }
+    setMinimized(init_minimize);
 
     // Other settings from the previous session
     if (session) {

src/xdgshellwindow.cpp

@@ -1377,9 +1377,7 @@ void XdgToplevelWindow::initialize()
     setOnActivities(rules()->checkActivity(activities(), true));
     setDesktops(rules()->checkDesktops(desktops(), true));
     setDesktopFileName(rules()->checkDesktopFile(desktopFileName(), true));
-    if (rules()->checkMinimize(isMinimized(), true)) {
-        minimize(true); // No animation.
-    }
+    setMinimized(rules()->checkMinimize(isMinimized(), true));
     setSkipTaskbar(rules()->checkSkipTaskbar(skipTaskbar(), true));
     setSkipPager(rules()->checkSkipPager(skipPager(), true));
     setSkipSwitcher(rules()->checkSkipSwitcher(skipSwitcher(), true));