import changes from `dev' branch of rmottola/Arctic-Fox:

- Bug 1253678 - Rename mozilla::Function to mozilla::function. r=froydnj (888553522d)
- Bug 1250788 - Part 2: Expose IsCSSSheetType method. r=bholley (7eb73ec696)
- Bug 1254943 - Set JS execution reason when invoking Promise callbacks. r=bz (212c135941)
- Bug 1175881 - about:sync-log can't read files on OS X with e10s on and content process sandbox enabled. r=areinald (52cf449634)
- Bug 1250788 - Part 3.1: Factor out CSSStyleSheetInner members so they can be used by ServoStyleSheet. r=bholley (4c50adcf26)
- Bug 1250788 - Part 3.2: Factor out CSSStyleSheet members so they can be used by ServoStyleSheet. r=bholley (7f09f8b56e)
- Bug 1250788 - Part 3.3: Implement enough of ServoStyleSheet for Loader to be able to create and parse one. r=bholley (7bb9e8bd47)
- Bug 1251496 - Hoist existing RefPtrTraits into a ServoBindingHelpers.h. r=heycam (c62ad77b46)
- Bug 1242690 - Ensure that mouse events have the callback transform applied. r=botond (296db0746b)
- Bug 1250788 - Part 1: Add interface to create and parse Servo style sheets. r=bholley (c50e5ada02)
- Bug 1250788 - Part 4: Implement enough of ServoStyleSet to handle the UA style sheets being added to it. r=bholley (d0ac9aa262)
- Bug 1250788 - Part 5: Create and parse ServoStyleSheets in css::Loader. r=bholley (25f6b1f8b9)
- Bug 1250788 - Part 6: Create ServoStyleSheets for the pref style sheet. r=bholley (275eb39243)
- Bug 1250788 - Unified build fix. (e52a27ef8d)
- Bug 1250379 - Create css::Loaders for specific style backend types. r=dholbert (a85f56226a)
- Bug 1256500 - Root style contexts before calling ApplyStyleFixups. r=heycam (1b47d3401c)
- Bug 1251496 - Introduce a servo-side data structure to represent the style set. r=heycam (956bd63b56)
- Bug 1252611 - Hoist mDocument into StyleSheet. r=dholbert (993664de79)
- Bug 1252611 - Add a method to get the StyleSheetInfo for a given StyleSheet. r=dholbert (59578e1bfc)
- Bug 1252611 - Hoist IsComplete/SetComplete into StyleSheet. r=dholbert (7e88b78d11)
- Preemptive unified build fix; no bug (100762c5c9)
- Bug 1239945 part 0 - Fix unified build (425e1109bf)
- Bug 1239945 part 1 - Drop a number of animation manager/collection-related methods that are unused (and in some cases undefined); r=dholbert (4d52514fe5)
- Bug 1239945 part 2 - Drop CommonAnimationManager::ContentOrAncestorHasAnimation; r=dholbert (ba0a919dcb)
- Bug 1239945 part 3 - Move AnimationCollection to a separate file; r=dholbert (b6af8d9ff3)
- Bug 1239945 part 4 - Remove the pointer from an AnimationCollection to its manager since it is no longer used; r=dholbert (875581afd5)
- Bug 1239945 part 5 - Use MayHaveAnimations() to return early in CommonAnimationManager::GetAnimationCollection; r=dholbert (aa4e1988e1)
- Bug 1242872 - Part 1: Introduce CSSAnimationBuilder to factor a bunch of stuff in BuildAnimations and CheckAnimationRule out. r=dbaron (25c1002b42)
- Bug 1242872 - Part 2: Set timeline in CSSAnimationBuilder::Build. r=dbaron (fd7461c6cb)
- Bug 1242872 - Part 3: Factor finding old animations process out. r=dbaron (901e5dadae)
- Bug 1242872 - Part 4: Factor updating animation properties process out. r=dbaron (deba9bbc34)
- Bug 1242872 - Part 5: Change CopyPropertiesFrom to UpdateProperties. r=birtles (26cfdf190b)
- Bug 1242872 - Part 6: Trigger a layer update explicitly when copying animation properties. r=birtles (8150212286)
- Bug 1242872 - Part 7: Eliminate creation of temporary animations. r=dbaron (24e0a5b79d)
- Bug 1242872 - Part 8: ElementPropertyTransition::ToValue(). r=birtles (2f21ea5887)
- Bug 1242872 - Part 1.1: Move AnimationManager::BuildAnimations. r=dbaron (6c51d5409d)
- Bug 1242872 - Part 9: Should not assume any order of animations in MurationObserver. r=pbrosset (910c5c0519)
- Bug 1239945 part 6 - Templatize AnimationCollection based on the concrete type of Animation stored; r=dholbert (bb37958019)
- Bug 1239945 part 7 - Move GetAnimationCollection to AnimationCollection; r=dholbert (e254079b58)
- Bug 1239945 part 8 - Add GetOrCreateAnimationCollection; r=dholbert (4e59c24fc1)
- Bug 1244641 - Part 1: Let AnimationEffectTiming have an effect. r=hiro (f2c4e43e80)
- Bug 1244641 - Part 2: Add duration implementation in dom/animation/AnimationEffectTiming.cpp. r=hiro, r=smaug (05819e6b8f)
- Bug 1244641 - Part 3: Notify animation mutation observers from AnimationEffectTiming::SetDuration. r=hiro (12ba42404a)
- Bug 1244080 - Part 0: Remove unnecessary argument for remove(). r=bbirtles (4753fd443d)
- Bug 1244080 - Part 1: Test that setting duration in the middle of the animation causes only once a restyling. r=bbirtles (64d568f0b2)
- Bug 1241692 - Part 1: Ensure that element which is added in each test is removed before subsequent test is processed. r=dholbert (890cce3bb3)
- Bug 1241692 - Part 2: We should observe stylings only for animations. r=dholbert (24e9497037)
- Bug 1218646 - Skip to check whether property can run on compositor or not if mWinsInCascade is false. r=birtles (f59232736b)
- Bug 1244641 - Part 4: Add duration tests in dom/animation/test/chrome. r=hiro (53fd5bdaf3)
- Bug 1244641 - Part 5: Add duration tests in layout/style/test. r=hiro (a5fd00fe51)
- Bug 1244641 - Part 6: Add duration tests in testing/web-platform/tests/web-animations. r=hiro (9ba57998ce)
- Bug 1257422 part 1. Add a way to do IDBObjectStore::OpenCursor without a JSContext if we are not passing a keyrange. r=khuey (a281fffd31)
- Bug 1257422 part 2. Use the overload of IDBRequest::GetResult that doesn't ask for a JSContext in FirstRevisionIdCallback::HandleEvent, since there is no reason not to. r=khuey (1d62d3da69)

xpcom/base/CycleCollectedJSRuntime.cpp

@@ -933,7 +933,7 @@ protected:
   NS_IMETHOD
   Run() override
   {
-    mCallback->Call();
+    mCallback->Call("promise callback");
     return NS_OK;
   }