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

- Bug 1182147: Ensure ImageHost does not attempt to call DrawQuad with an effect unsupported by the compositor. r=nical (5624e9134f)
- Bug 1151749 - "Win-Only: Disabled Hardware Acceleration + CSS 3D transform on canvas -> black artefacts on hover". r=nical (54c49071b9)
- Bug 1184224 - Remove gfxPrefs.h include from gfxPlatformGtk.h. r=karlt (eb907daa58)
- Bug 1183820 - Expose if cairo uses XRender to GetAzureBackendInfo. r=mattwoodrow (10044ecfb0)
- Bug 1128934 - Call XFlush after compositing to prevent jank. r=karlt (f63b9dc1b5)
- Bug 1151663 - New mochitest for this bug. r=kats (9344d22ed6)
- Bug 1176402 - Have synthesizeNativeWheel() and synthesizeNativeMouseMove() accept coordinates relative to the element's bounding rect. r=kats (cbdffe3869)
- Bug 1177018 - Work around the iframe in which mochitests are run not being scrollable. r=kats (d24291080c)
- Bug 1177018 - Disable smooth scrolling in the APZ layerization test. r=kats (e1af545da1)
- Bug 1181678 - Improve the check for skipping test_layerization if APZ is disabled. r=botond (91e5ead610)
- Bug 1177018 - Enable chaos mode for the APZ layerization test. r=kats (f07fdeb936)
- Bug 1177018 - Only enable APZ test logging for tests that actually use it. r=kats (9f24ea01c4)
- Bug 1196294 - Remove the mCause from TimelineMarkers, r=tromey (5abd1c057d)
- Bug 1195232 - Stop using TracingMetadata from GeckoProfiler.h, r=tromey (e736038873)
- Bug 1200118 - Create a barebones TimelineMarker abstract class, r=tromey (9930c83c2f)
- Bug 1200252 - Add marker for when the IPC request for a composite is sent to the compositor thread, r=jsantell,matt (becc11f58b)
- align some minor thing to gecko (5bb64e322a)
- Bug 1204581 - Add a deprecation warning for the usage of AppCache when service worker fetch interception is enabled; r=mcmanus,baku (69949c8d96)
- Bug 1210941 P2 Use LOAD_BYPASS_SERVICE_WORKER in HttpBaseChannel instead of mForceNoIntercept. r=jduell (fdb7afc0be)
- Bug 1173171 - Disable external jar: via preference. r=jduell (704cfb0b9c)
- Bug 1210941 P3 Make jar channels use LOAD_BYPASS_SERVICE_WORKER internally. r=jduell (d871dc4837)
- Bug 1210941 P4 Use LOAD_BYPASS_SERVICE_WORKER instead of ForceNoIntercept in nsDocShell. r=ehsan (ea5ed76717)
- Bug 1210941 P5 Use LOAD_BYPASS_SERVICE_WORKER in nsObjectLoadingContent instead of ForceNoIntercept(). r=ehsan (9e821adfaa)
- Bug 1210941 P6 Use LOAD_BYPASS_SERVICE_WORKER instead of ForceNoIntercept in FetchDriver. r=ehsan (02685be882)
- Bug 1210941 P7 Use LOAD_BYPASS_SERVICE_WORKER in ServiceWorkerScriptCache. r=ehsan (45fa163dd2)
- Bug 1182112 - XML documents should not be intercepted by ServiceWorkers. r=ehsan (a9dfeffcb3)
- Bug 1210941 P8 Use LOAD_BYPASS_SERVICE_WORKER in xslt txURIUtils. r=ehsan (d7686d572b)
- Bug 1210941 P9 Use LOAD_BYPASS_SERVICE_WORKER in nsCORSListenerProxy. r=ehsan (653f50de45)
- Bug 1205302 - Disallow intercepting OCSP requests; r=jdm (b4650e78d9)
- Bug 1210941 P10 Use LOAD_BYPASS_SERVICE_WORKER in nsNSSCallbacks. r=ehsan (b4b8b3f503)
- Bug 1210941 P11 Use LOAD_BYPASS_SERVICE_WORKER in worker ScriptLoader. r=ehsan (ac07404832)
- Bug 1210941 P12 Remove http channel's ForceNoIntercept. r=jduell IGNORE IDL (a7592a83c4)
- Bug 1210941 P13 Remove ForceNoIntercept from jar channel. r=jduell (617544fcee)
- Bug 1169613 - Use content type of synthesized response for JAR channel requests if available. Part 1: Set Content-Type of synthesized reponses for JAR channel requests. r=jdm (e32061a26a)
- Bug 1169613 - Use content type of synthesized response for JAR channel requests if available. Part 2: Set Content-Type for JAR Channel requests on Fetch API responses. r=nsm (da43e29583)
- Bug 1207556 - Part 1: Stop reusing the loadinfo in StartCORSPreflight; r=sicking (4724bfa8cd)
- Bug 1207556 - Part 2: Fix the beacon CORS preflight tests; r=sicking (c61a699f9f)
- Bug 1111834 - CORS preflight of navigator.sendBeacon() should not follow 30x redirect - tests. r=sicking (2871ad22e7)
- fix build because of previous backports (e3096e6f9a)
- Bug 1161677 - Expose dev mode state read-only through the navigator.hasFeature() api r=ehsan (013399847b)
- Bug 1203680 P8 nsCORSListenerProxy::OnStartRequest must always call outer OnStartRequest. r=ehsan (9a67709770)
- spacing (d4511b37c4)
- missing bit of 920017 and some telemetry (2bf267ce72)

gfx/layers/client/ClientLayerManager.cpp

@@ -231,9 +231,14 @@ ClientLayerManager::BeginTransactionWithTarget(gfxContext* aTarget)
   }
 
   // If this is a new paint, increment the paint sequence number.
-  if (!mIsRepeatTransaction && gfxPrefs::APZTestLoggingEnabled()) {
+  if (!mIsRepeatTransaction) {
+    // Increment the paint sequence number even if test logging isn't
+    // enabled in this process; it may be enabled in the parent process,
+    // and the parent process expects unique sequence numbers.
     ++mPaintSequenceNumber;
-    mApzTestData.StartNewPaint(mPaintSequenceNumber);
+    if (gfxPrefs::APZTestLoggingEnabled()) {
+      mApzTestData.StartNewPaint(mPaintSequenceNumber);
+    }
   }
 }
 
@@ -509,7 +514,7 @@ ClientLayerManager::MakeSnapshotIfRequired()
         gfx::Matrix rotate = ComputeTransformForUnRotation(outerBounds, mTargetRotation);
 
         gfx::Matrix oldMatrix = dt->GetTransform();
-        dt->SetTransform(oldMatrix * rotate);
+        dt->SetTransform(rotate * oldMatrix);
         dt->DrawSurface(surf, dstRect, srcRect,
                         DrawSurfaceOptions(),
                         DrawOptions(1.0f, CompositionOp::OP_OVER));
@@ -566,6 +571,8 @@ ClientLayerManager::StopFrameTimeRecording(uint32_t         aStartIndex,
 void
 ClientLayerManager::ForwardTransaction(bool aScheduleComposite)
 {
+  TimeStamp start = TimeStamp::Now();
+
   if (mForwarder->GetSyncObject()) {
     mForwarder->GetSyncObject()->FinalizeFrame();
   }
@@ -640,6 +647,12 @@ ClientLayerManager::ForwardTransaction(bool aScheduleComposite)
   // this may result in Layers being deleted, which results in
   // PLayer::Send__delete__() and DeallocShmem()
   mKeepAlive.Clear();
+
+  TabChild* window = mWidget->GetOwningTabChild();
+  if (window) {
+    TimeStamp end = TimeStamp::Now();
+    window->DidRequestComposite(start, end);
+  }
 }
 
 ShadowableLayer*