Fix the slint_mock_elapsed_time when not using the testing backend

The nodejs tests don't use the testing backend, as a result, calling
`platform::update_timers_and_animations` would use the real time instead
of the fake time.
So call `maybe_activate_timers` with the fake time instead

internal/core/platform.rs

@@ -166,7 +166,7 @@ pub fn set_platform(platform: Box<dyn Platform + 'static>) -> Result<(), SetPlat
 /// This function should be called before rendering or processing input event, at the
 /// beginning of each event loop iteration.
 pub fn update_timers_and_animations() {
-    crate::timers::TimerList::maybe_activate_timers();
+    crate::timers::TimerList::maybe_activate_timers(crate::animations::Instant::now());
     crate::animations::update_animations();
 }
 

internal/core/tests.rs

@@ -16,12 +16,13 @@ use crate::SharedString;
 /// This function will add some milliseconds to the fake time
 #[no_mangle]
 pub extern "C" fn slint_mock_elapsed_time(time_in_ms: u64) {
-    crate::animations::CURRENT_ANIMATION_DRIVER.with(|driver| {
+    let tick = crate::animations::CURRENT_ANIMATION_DRIVER.with(|driver| {
         let mut tick = driver.current_tick();
         tick += core::time::Duration::from_millis(time_in_ms);
-        driver.update_animations(tick)
+        driver.update_animations(tick);
+        tick
     });
-    crate::platform::update_timers_and_animations();
+    crate::timers::TimerList::maybe_activate_timers(tick);
 }
 
 /// Simulate a click on a position within the component.

internal/core/timers.rs

@@ -214,8 +214,7 @@ impl TimerList {
 
     /// Activates any expired timers by calling their callback function. Returns true if any timers were
     /// activated; false otherwise.
-    pub fn maybe_activate_timers() -> bool {
-        let now = Instant::now();
+    pub fn maybe_activate_timers(now: Instant) -> bool {
         // Shortcut: Is there any timer worth activating?
         if TimerList::next_timeout().map(|timeout| now < timeout).unwrap_or(false) {
             return false;