[iOS] Inject DisplayLinkManager into VsyncWaiterIOS#189749
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This pull request refactors VsyncWaiterIOS to accept an injected FlutterDisplayLinkManager instance instead of relying on the shared singleton, which improves testability. It also adds unit tests to verify the behavior with the injected manager. The feedback suggests adding a defensive assertion (FML_DCHECK) in the constructor to ensure the injected display_link_manager is not null.
This is a follow-up to flutter#189492, which migrated `DisplayLinkManager` to a shared singleton instance. `VsyncWaiterIOS` was using `.shared` directly in three places internally, which is effectively using a hidden global, and it means the only way to exercise `VsyncWaiterIOS` against a non-default refresh rate was to mutate the real shared instance out from under whatever else might be touching it. This wires a `FlutterDisplayLinkManager*` through the constructor instead and stores a private reference. I've also added two tests, which required making `AwaitVSync()` accessible again; I accidentally marked it private in flutter#186935 (722be07) when adding SnapDuration (despite my comment saying it was made public for testing), so restored it to public. Issue: flutter#175879 Issue: flutter#181684
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flutter/flutter@cab057d...1ac2e82 2026-07-21 [email protected] Add BaseWindowController.isDestroyed flag (flutter/flutter#189061) 2026-07-21 [email protected] Roll Dart SDK from 666e1e2133b7 to 3b2f5ad7718d (1 revision) (flutter/flutter#189745) 2026-07-21 [email protected] Roll Skia from 3c52d80c960d to 569534e9fa59 (5 revisions) (flutter/flutter#189766) 2026-07-21 [email protected] Roll Skia from 11426cf7aaa1 to 3c52d80c960d (2 revisions) (flutter/flutter#189758) 2026-07-21 [email protected] Roll pub packages (flutter/flutter#189760) 2026-07-21 [email protected] [iOS] Inject DisplayLinkManager into FlutterKeyboardInsetManager (flutter/flutter#189751) 2026-07-21 [email protected] Treat package:stack_trace async-gap marker as asynchronous suspension (flutter/flutter#185791) 2026-07-21 [email protected] [iOS] Inject DisplayLinkManager into VsyncWaiterIOS (flutter/flutter#189749) 2026-07-20 [email protected] Use String builder in `InputConnectionAdaptorTest.java` (flutter/flutter#189281) 2026-07-20 [email protected] Fix non-independant tests in draggable_test.dart (flutter/flutter#186898) 2026-07-20 [email protected] Stop using ReLinker to load libflutter.so on Android 17 (API 37+) (flutter/flutter#189146) 2026-07-20 [email protected] [et] Refactor gn post-processing, fix minor clang[++] regex match bug (flutter/flutter#189685) 2026-07-20 [email protected] Take plugin_test_darwin out of bringup (flutter/flutter#189594) 2026-07-20 [email protected] Roll pub packages (flutter/flutter#189596) 2026-07-20 [email protected] widgets layer re-export ScrollCacheExtent (flutter/flutter#189483) 2026-07-20 [email protected] Roll Skia from 47143b6fa402 to 11426cf7aaa1 (7 revisions) (flutter/flutter#189740) 2026-07-20 [email protected] Sync CHANGELOG.md from stable (flutter/flutter#189735) 2026-07-20 [email protected] [Impeller] In the AHBTextureSourceVK destructor, do not call Vulkan APIs if the VkDevice has been destroyed (flutter/flutter#189666) 2026-07-20 [email protected] Add AutofillHints.emailOTPCode for Android AUTOFILL_HINT_EMAIL_OTP (flutter/flutter#188123) 2026-07-20 [email protected] Add a github workflow to remove flutteractionsbot branches after the PRs are merged or closed. (flutter/flutter#189668) 2026-07-20 [email protected] Roll ANGLE to cc08479fbcc1 (flutter/flutter#189595) 2026-07-20 [email protected] Roll Fuchsia Linux SDK from NL8xtzr8cxr5E8r8E... to GswhlPRO-D1qSNclx... (flutter/flutter#189715) 2026-07-20 [email protected] Roll Skia from ba90f98535de to 47143b6fa402 (4 revisions) (flutter/flutter#189721) If this roll has caused a breakage, revert this CL and stop the roller using the controls here: https://autoroll.skia.org/r/flutter-packages Please CC [email protected],[email protected] on the revert to ensure that a human is aware of the problem. To file a bug in Packages: https://github.com/flutter/flutter/issues/new/choose To report a problem with the AutoRoller itself, please file a bug: https://issues.skia.org/issues/new?component=1389291&template=1850622 Documentation for the AutoRoller is here: https://skia.googlesource.com/buildbot/+doc/main/autoroll/README.md
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This is a follow-up to #189492, which migrated
DisplayLinkManagerto a shared singleton instance.VsyncWaiterIOSwas using.shareddirectly in three places internally, which is effectively using a hidden global, and it means the only way to exerciseVsyncWaiterIOSagainst a non-default refresh rate was to mutate the real shared instance out from under whatever else might be touching it.This wires a
FlutterDisplayLinkManager*through the constructor instead and stores a private reference.I've also added two tests, which required making
AwaitVSync()accessible again; I accidentally marked it private in #186935 (722be07) when adding SnapDuration (despite my comment saying it was made public for testing), so restored it to public.Issue: #175879
Issue: #181684
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