From eaee1dbb37e59160969c69687419d81c78b28b9f Mon Sep 17 00:00:00 2001
From: Bobby Holley <bobbyholley@gmail.com>
Date: Wed, 15 Feb 2017 19:36:57 -0800
Subject: [PATCH] Bug 1340022 - Implement "handled for descendants" tracking
 for RestyleDamage. r=emilio

MozReview-Commit-ID: Bbk99ogILXC

--HG--
extra : rebase_source : 2998f39a67c39073ea66e3e12815e1a7a25f7c9d
---
 layout/base/nsChangeHint.h     | 2 ++
 layout/style/ServoBindings.cpp | 6 ++++++
 layout/style/ServoBindings.h   | 1 +
 3 files changed, 9 insertions(+)

diff --git a/layout/base/nsChangeHint.h b/layout/base/nsChangeHint.h
index 0f064eca40ea..8df4c63f4cce 100644
--- a/layout/base/nsChangeHint.h
+++ b/layout/base/nsChangeHint.h
@@ -319,6 +319,8 @@ inline nsChangeHint operator^=(nsChangeHint& aLeft, nsChangeHint aRight)
           nsChangeHint_UpdateUsesOpacity | \
           nsChangeHint_UpdateBackgroundPosition)
 
+// NB: Once we drop support for the old style system, this logic should be
+// inlined in the Servo style system to eliminate the FFI call.
 inline nsChangeHint NS_HintsNotHandledForDescendantsIn(nsChangeHint aChangeHint) {
   nsChangeHint result = nsChangeHint(aChangeHint & (
     nsChangeHint_UpdateTransformLayer |
diff --git a/layout/style/ServoBindings.cpp b/layout/style/ServoBindings.cpp
index 0f46e90bc6bb..d3d23566719a 100644
--- a/layout/style/ServoBindings.cpp
+++ b/layout/style/ServoBindings.cpp
@@ -310,6 +310,12 @@ Gecko_CalcStyleDifference(nsStyleContext* aOldStyleContext,
   return result;
 }
 
+nsChangeHint
+Gecko_HintsHandledForDescendants(nsChangeHint aHint)
+{
+  return aHint & ~NS_HintsNotHandledForDescendantsIn(aHint);
+}
+
 ServoElementSnapshotOwned
 Gecko_CreateElementSnapshot(RawGeckoElementBorrowed aElement)
 {
diff --git a/layout/style/ServoBindings.h b/layout/style/ServoBindings.h
index 6fd24326e201..f8403e4dd749 100644
--- a/layout/style/ServoBindings.h
+++ b/layout/style/ServoBindings.h
@@ -243,6 +243,7 @@ nsStyleContext* Gecko_GetStyleContext(RawGeckoNodeBorrowed node,
                                       nsIAtom* aPseudoTagOrNull);
 nsChangeHint Gecko_CalcStyleDifference(nsStyleContext* oldstyle,
                                        ServoComputedValuesBorrowed newstyle);
+nsChangeHint Gecko_HintsHandledForDescendants(nsChangeHint aHint);
 
 // Element snapshot.
 ServoElementSnapshotOwned Gecko_CreateElementSnapshot(RawGeckoElementBorrowed element);