Bug 1273042 - Part 1: Use StyleContext()->GetPseudoType() to obtain CSSPseudoElementType for the nsIFrame. r=birtles

Before this patch, we could't use EffectSet::GetEffectSet(nsIFrame*) until
the target content associated with the nsIFrame has a primary frame since
nsLayoutUtils::GetStyleFrame(nsIContent*) needs the primary frame.

In this patch, StyleContext()->GetPseudoType() is used for obtaining
CSSPseudoElementType instread of content->NodeInfo()->NameAtom().
As a result, we don't need to care about whether the content has a
primary frame or not.

dom/animation/EffectCompositor.cpp

@@ -519,35 +519,26 @@ EffectCompositor::GetAnimationElementAndPseudoForFrame(const nsIFrame* aFrame)
   // Always return the same object to benefit from return-value optimization.
   Maybe<NonOwningAnimationTarget> result;
 
+  CSSPseudoElementType pseudoType =
+    aFrame->StyleContext()->GetPseudoType();
+
+  if (pseudoType != CSSPseudoElementType::NotPseudo &&
+      pseudoType != CSSPseudoElementType::before &&
+      pseudoType != CSSPseudoElementType::after) {
+    return result;
+  }
+
   nsIContent* content = aFrame->GetContent();
   if (!content) {
     return result;
   }
 
-  CSSPseudoElementType pseudoType = CSSPseudoElementType::NotPseudo;
-
-  if (aFrame->IsGeneratedContentFrame()) {
-    nsIFrame* parent = aFrame->GetParent();
-    if (parent->IsGeneratedContentFrame()) {
-      return result;
-    }
-    nsIAtom* name = content->NodeInfo()->NameAtom();
-    if (name == nsGkAtoms::mozgeneratedcontentbefore) {
-      pseudoType = CSSPseudoElementType::before;
-    } else if (name == nsGkAtoms::mozgeneratedcontentafter) {
-      pseudoType = CSSPseudoElementType::after;
-    } else {
-      return result;
-    }
+  if (pseudoType == CSSPseudoElementType::before ||
+      pseudoType == CSSPseudoElementType::after) {
     content = content->GetParent();
     if (!content) {
       return result;
     }
-  } else {
-    if (nsLayoutUtils::GetStyleFrame(content) != aFrame) {
-      // The effects associated with an element are for its primary frame.
-      return result;
-    }
   }
 
   if (!content->IsElement()) {

dom/animation/EffectSet.cpp

@@ -49,42 +49,18 @@ EffectSet::GetEffectSet(dom::Element* aElement,
 /* static */ EffectSet*
 EffectSet::GetEffectSet(const nsIFrame* aFrame)
 {
-  nsIContent* content = aFrame->GetContent();
-  if (!content) {
+  Maybe<NonOwningAnimationTarget> target =
+    EffectCompositor::GetAnimationElementAndPseudoForFrame(aFrame);
+
+  if (!target) {
     return nullptr;
   }
 
-  nsIAtom* propName;
-  if (aFrame->IsGeneratedContentFrame()) {
-    nsIFrame* parent = aFrame->GetParent();
-    if (parent->IsGeneratedContentFrame()) {
-      return nullptr;
-    }
-    nsIAtom* name = content->NodeInfo()->NameAtom();
-    if (name == nsGkAtoms::mozgeneratedcontentbefore) {
-      propName = nsGkAtoms::animationEffectsForBeforeProperty;
-    } else if (name == nsGkAtoms::mozgeneratedcontentafter) {
-      propName = nsGkAtoms::animationEffectsForAfterProperty;
-    } else {
-      return nullptr;
-    }
-    content = content->GetParent();
-    if (!content) {
-      return nullptr;
-    }
-  } else {
-    if (nsLayoutUtils::GetStyleFrame(content) != aFrame) {
-      // The effects associated with an element are for its primary frame.
-      return nullptr;
-    }
-    propName = nsGkAtoms::animationEffectsProperty;
-  }
-
-  if (!content->MayHaveAnimations()) {
+  if (!target->mElement->MayHaveAnimations()) {
     return nullptr;
   }
 
-  return static_cast<EffectSet*>(content->GetProperty(propName));
+  return GetEffectSet(target->mElement, target->mPseudoType);
 }
 
 /* static */ EffectSet*