Use counter submission normally happens at document destruction. For
testing use counters, however, we need to have use counters updated in
telemetry at deterministic points. Therefore, we provide a method on
nsIDOMWindowUtils that forces use counters out to telemetry so we can
examine them.
This is motivated by three separate but related problems:
1. Our concept of recursion depth is broken for things that run from AfterProcessNextEvent observers (e.g. Promises). We decrement the recursionDepth counter before firing observers, so a Promise callback running at the lowest event loop depth has a recursion depth of 0 (whereas a regular nsIRunnable would be 1). This is a problem because it's impossible to distinguish a Promise running after a sync XHR's onreadystatechange handler from a top-level event (since the former runs with depth 2 - 1 = 1, and the latter runs with just 1).
2. The nsIThreadObserver mechanism that is used by a lot of code to run "after" the current event is a poor fit for anything that runs script. First, the order the observers fire in is the order they were added, not anything fixed by spec. Additionally, running script can cause the event loop to spin, which is a big source of pain here (bholley has some nasty bug caused by this).
3. We run Promises from different points in the code for workers and main thread. The latter runs from XPConnect's nsIThreadObserver callbacks, while the former runs from a hardcoded call to run Promises in the worker event loop. What workers do is particularly problematic because it means we can't get the right recursion depth no matter what we do to nsThread.
The solve this, this patch does the following:
1. Consolidate some handling of microtasks and all handling of stable state from appshell and WorkerPrivate into CycleCollectedJSRuntime.
2. Make the recursionDepth counter only available to CycleCollectedJSRuntime (and its consumers) and remove it from the nsIThreadInternal and nsIThreadObserver APIs.
3. Adjust the recursionDepth counter so that microtasks run with the recursionDepth of the task they are associated with.
4. Introduce the concept of metastable state to replace appshell's RunBeforeNextEvent. Metastable state is reached after every microtask or task is completed. This provides the semantics that bent and I want for IndexedDB, where transactions autocommit at the end of a microtask and do not "spill" from one microtask into a subsequent microtask. This differs from appshell's RunBeforeNextEvent in two ways:
a) It fires between microtasks, which was the motivation for starting this.
b) It no longer ensures that we're at the same event loop depth in the native event queue. bent decided we don't care about this.
5. Reorder stable state to happen after microtasks such as Promises, per HTML. Right now we call the regular thread observers, including appshell, before the main thread observer (XPConnect), so stable state tasks happen before microtasks.
Rather than store a non-thread-safe refcounted nsIStructuredCloneContainer, store the base64 representation.
Caches a jsval the first time an attempt to access data is made from content script.
--HG--
extra : commitid : Ijd82LTJaYo
extra : rebase_source : f82e837842037ea02efae3a0fc9b2b35c2a0d7d0
Refactoring to allow access to PushManager in ServiceWorkerGlobalScope. See comment in PushManager.h for details.
--HG--
extra : commitid : A7RvB9rm8av
extra : transplant_source : %20%99%CA%B0%EB%B9%82%27D%F7e%B8UQ%12%E6%9B%18%BB5
Fix xpcshell tests.
Add support for webapps-clear-data.
Trash old regs on idb version upgrade.
Use principal for permission check.
use principal in PushSubscription.
--HG--
extra : source : d7554019b424327a3271e2c0debda995fff36cb5
extra : intermediate-source : be40dea6534771bdeedc9f7c6ccd8bbddb6e41c2
Fix xpcshell tests.
Add support for webapps-clear-data.
Trash old regs on idb version upgrade.
Use principal for permission check.
use principal in PushSubscription.
--HG--
extra : rebase_source : 3b8cb541512d3fb9a253773c2fd5227c980efdd2
extra : source : d7554019b424327a3271e2c0debda995fff36cb5
I claim this code is dead because on the one hand it's no longer called from JS
(because Window is always on WebIDL bindings, but on the other hand it can't
really be called from C++ because it depends on examining the XPConnect call
information.
I think removing this completely, including from the IDL, is safe, because
nothing directly returns nsIDOMJSWindow, so anyone using its vtable would have
to QI to it and we're changing the IID.
Fabrice Desré
Masayuki Nakano
Tim Chien
Ryan VanderMeulen
Benoit Girard
Kartikaya Gupta
Nathan Froyd
Matt Woodrow
Brad Lassey
Aryeh Gregor
Kyle Huey
L. David Baron
Nikhil Marathe
Blake Kaplan
Neil Deakin
Carsten "Tomcat" Book
Boris Zbarsky
Ben Kelly
Bobby Holley
Christoph Kerschbaumer
Cameron McCormack
Lee Salzman
Franziskus Kiefer
Jan Varga
Andrea Marchesini
Yoshi Huang
Karl Tomlinson