iOS: Always set timer when polling to avoid slow waking (#2979)

* Always set timer when polling to avoid slow waking

* add comment and changelog

---------

Co-authored-by: Dusty DeWeese <dustin.deweese@gmail.com>
Co-authored-by: Mads Marquart <mads@marquart.dk>

CHANGELOG.md

@@ -8,6 +8,7 @@ And please only add new entries to the top of this list, right below the `# Unre
 
 # Unreleased
 
+- On iOS, always wake the event loop when transitioning from `ControlFlow::Poll` to `ControlFlow::Poll`.
 - **Breaking:** `ActivationTokenDone` event which could be requested with the new `startup_notify` module, see its docs for more.
 - On Wayland, make double clicking and moving the CSD frame more reliable.
 - On macOS, add tabbing APIs on `WindowExtMacOS` and `EventLoopWindowTargetExtMacOS`.

src/platform_impl/ios/app_state.rs

@@ -393,9 +393,6 @@ impl AppState {
 
         let new = self.control_flow;
         match (old, new) {
-            (ControlFlow::Poll, ControlFlow::Poll) => self.set_state(AppStateImpl::PollFinished {
-                waiting_event_handler,
-            }),
             (ControlFlow::Wait, ControlFlow::Wait) => {
                 let start = Instant::now();
                 self.set_state(AppStateImpl::Waiting {
@@ -428,6 +425,7 @@ impl AppState {
                 });
                 self.waker.start_at(new_instant)
             }
+            // Unlike on macOS, handle Poll to Poll transition here to call the waker
             (_, ControlFlow::Poll) => {
                 self.set_state(AppStateImpl::PollFinished {
                     waiting_event_handler,