Bug 1846516 - Minor fix ups and logical animation clean-up. r=zrhoffman

Differential Revision: https://phabricator.services.mozilla.com/D196341

layout/style/AnimatedPropertyID.h

@@ -23,19 +23,21 @@ struct AnimatedPropertyID {
   }
 
   explicit AnimatedPropertyID(RefPtr<nsAtom> aCustomName)
-      : mID(eCSSPropertyExtra_variable), mCustomName(std::move(aCustomName)) {}
+      : mID(eCSSPropertyExtra_variable), mCustomName(std::move(aCustomName)) {
+    MOZ_ASSERT(mCustomName, "Null custom property name");
+  }
 
   nsCSSPropertyID mID = eCSSProperty_UNKNOWN;
   RefPtr<nsAtom> mCustomName;
 
   bool IsCustom() const { return mID == eCSSPropertyExtra_variable; }
   bool operator==(const AnimatedPropertyID& aOther) const {
-    return mID == aOther.mID &&
-           (!IsCustom() || mCustomName == aOther.mCustomName);
+    return mID == aOther.mID && mCustomName == aOther.mCustomName;
   }
   bool operator!=(const AnimatedPropertyID& aOther) const {
     return !(*this == aOther);
   }
+
   bool IsValid() const {
     if (mID == eCSSProperty_UNKNOWN) {
       return false;
@@ -56,8 +58,24 @@ struct AnimatedPropertyID {
     HashNumber hash = mCustomName ? mCustomName->hash() : 0;
     return AddToHash(hash, mID);
   }
+
+  AnimatedPropertyID ToPhysical(const ComputedStyle& aStyle) const {
+    if (IsCustom()) {
+      return *this;
+    }
+    return AnimatedPropertyID{nsCSSProps::Physicalize(mID, aStyle)};
+  }
 };
 
+// MOZ_DBG support for AnimatedPropertyId
+inline std::ostream& operator<<(std::ostream& aOut,
+                                const AnimatedPropertyID& aProperty) {
+  if (aProperty.IsCustom()) {
+    return aOut << nsAtomCString(aProperty.mCustomName);
+  }
+  return aOut << nsCSSProps::GetStringValue(aProperty.mID);
+}
+
 }  // namespace mozilla
 
 #endif  // mozilla_AnimatedPropertyID_h

layout/style/nsTransitionManager.cpp

@@ -72,6 +72,7 @@ static void ExpandTransitionProperty(nsCSSPropertyID aProperty,
 
   if (aProperty == eCSSPropertyExtra_variable) {
     AnimatedPropertyID property(aCustomName);
+    aHandler(property);
     return;
   }
 
@@ -142,14 +143,12 @@ bool nsTransitionManager::DoUpdateTransitions(
     AnimatedPropertyIDSet allTransitionProperties;
     if (checkProperties) {
       for (uint32_t i = aStyle.mTransitionPropertyCount; i-- != 0;) {
-        ExpandTransitionProperty(
-            aStyle.GetTransitionProperty(i),
-            aStyle.GetTransitionUnknownProperty(i),
-            [&](const AnimatedPropertyID& aProperty) {
-              AnimatedPropertyID property = aProperty;
-              property.mID = nsCSSProps::Physicalize(aProperty.mID, aNewStyle);
-              allTransitionProperties.AddProperty(aProperty);
-            });
+        ExpandTransitionProperty(aStyle.GetTransitionProperty(i),
+                                 aStyle.GetTransitionUnknownProperty(i),
+                                 [&](const AnimatedPropertyID& aProperty) {
+                                   allTransitionProperties.AddProperty(
+                                       aProperty.ToPhysical(aNewStyle));
+                                 });
       }
     }
 
@@ -267,10 +266,7 @@ bool nsTransitionManager::ConsiderInitiatingTransition(
       !aElementTransitions || &aElementTransitions->mElement == aElement,
       "Element mismatch");
 
-  AnimatedPropertyID property = aProperty;
-  if (!property.IsCustom()) {
-    property.mID = nsCSSProps::Physicalize(property.mID, aNewStyle);
-  }
+  AnimatedPropertyID property = aProperty.ToPhysical(aNewStyle);
 
   // A later item in transition-property already specified a transition for
   // this property, so we ignore this one.
@@ -317,7 +313,7 @@ bool nsTransitionManager::ConsiderInitiatingTransition(
   AnimationValue startValue, endValue;
   const StyleShouldTransitionResult result =
       Servo_ComputedValues_ShouldTransition(
-          &aOldStyle, &aNewStyle, &aProperty,
+          &aOldStyle, &aNewStyle, &property,
           oldTransition ? oldTransition->ToValue().mServo.get() : nullptr,
           &startValue.mServo, &endValue.mServo);