This change is part of an LSC in Fuchsia, and is a functionality no-op.

Fixes fxbug.dev/50759
Co-authored-by: NGabriel Schine <thatguy@google.com>

This reverts commit a5e0b2f2.

The way transactions were added changed in
https://github.com/flutter/engine/commit/68fd8334889610af08cbfc2828f91cf14faf3f1d.
This broke rendering using both Metal and OpenGL when no implicit transaction
was present on the transaction stack. The failure models differ based on Metal
vs. OpenGL and iOS/device versions. On older versions of iOS, rendering would
consume memory till exhaustion. On newer iOS versions, rendering would be stuck
(till a timeout). This patch brings transaction management back in line with as
it was earlier and also makes the Metal backend resilient to transactions being
present on the transaction stack at all. Since this is still quite brittle,
transaction management must be moved to IOSSurface as a followup.

Fixes https://github.com/flutter/flutter/issues/55784.

* Revert "Do not register UI-related native functions in secondary isolates (#6401)"

This reverts commit 69ae5694 as it doesn't work when root and secondary isolates run in the same isolate group.

* Confirm it is root isolate that makes UI native calls.

* Fix format, UIDartState reference from Fuchsia source

* No UI isolate check for fuchsia calls

* Fix typo. Remove redundant runtime calls

In order to better support different products on Fuchsia, we should
change performance-sensitive attributes based on config files passed in.
This change does so for `vsync_offset`.

When creating a console on Windows, stdout/stderr aren't wired up to it.
They need to be re-opened afeter the console is created, and that needs
to be done separately in the engine due to the use of static runtime
linking. This provides a helper method that the runner can call when
creating a console so that output will work as expected.

Part of https://github.com/flutter/flutter/issues/53169

Bundle the validation layers and enable them if --enable-vulkan-validation-layers is specified to gn (#17854)

This is to reduce log spam.

Fixes: https://github.com/flutter/flutter/issues/55966

This functionality is added in issue #41523.  Allows runners to request
the singleton instance of `sys::ComponentContext`, while it remains also
accessible to component-specific code that does not have direct access
to top-level objects.

Fixes #41523

The existing logic incorrectly factored out a check that there were arguments too early, applying it to any message not already handled (including unhandled methods, such as methods added after the initial implementation) and thus failing if any unhandled message had no arguments.

Fixes https://github.com/flutter/flutter/issues/55653

Fixes https://github.com/flutter/flutter/issues/55783
Requires follow-up https://github.com/flutter/flutter/issues/55926

Fixes https://github.com/flutter/flutter/issues/54856

GTK uses timestamps in milliseconds, Flutter wants them in microseconds.

This reverts commit a544b45f.

Reverts flutter/engine#17878

This breaks our devicelab tests.

TBR: @flar 

This change converts it from an events that spans a time interval
to an event that occurs at an instant.

We also emit this trace event when there is no lag as opposed to
only when there was a lag to make it monotonous.
Co-authored-by: NKaushik Iska <kaushikiska@google.com>

Fixes https://github.com/flutter/flutter/issues/55219