Bug 1341985 - Update CSS animations in a SequentialTask. r=heycam

We create the SequentialTask only if:

* We have no old computed values and we have animation name style in the new
  computed values.
* Any animation properties is changed.
* display property is changed from 'none' and we have animation name style.
* display property is changed to 'none'.

In a subsequent patch we skip the SequentialTask if we have no running
animations and the display propery is changed to 'none'.

MozReview-Commit-ID: JRSZznufOS2

--HG--
extra : rebase_source : 566026c21c6357f77df55e3bd588835f5fd6c3d4

layout/style/ServoBindings.cpp

@@ -8,6 +8,7 @@
 
 #include "ChildIterator.h"
 #include "gfxFontFamilyList.h"
+#include "nsAnimationManager.h"
 #include "nsAttrValueInlines.h"
 #include "nsCSSFrameConstructor.h"
 #include "nsCSSProps.h"
@@ -431,6 +432,28 @@ Gecko_StyleAnimationsEquals(RawGeckoStyleAnimationListBorrowed aA,
   return *aA == *aB;
 }
 
+void
+Gecko_UpdateAnimations(RawGeckoElementBorrowed aElement,
+                       nsIAtom* aPseudoTagOrNull,
+                       ServoComputedValuesBorrowed aComputedValues,
+                       ServoComputedValuesBorrowedOrNull aParentComputedValues)
+{
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(aElement);
+  MOZ_ASSERT(aComputedValues);
+
+  nsPresContext* presContext = nsContentUtils::GetContextForContent(aElement);
+  if (!presContext) {
+    return;
+  }
+
+  if (presContext->IsDynamic() && aElement->IsInComposedDoc()) {
+    presContext->AnimationManager()->
+      UpdateAnimations(const_cast<dom::Element*>(aElement), aPseudoTagOrNull,
+                       aComputedValues, aParentComputedValues);
+  }
+}
+
 void
 Gecko_FillAllBackgroundLists(nsStyleImageLayers* aLayers, uint32_t aMaxLen)
 {

layout/style/ServoBindings.h

@@ -193,6 +193,10 @@ Gecko_GetAnimationRule(RawGeckoElementBorrowed aElement,
                        mozilla::EffectCompositor::CascadeLevel aCascadeLevel);
 bool Gecko_StyleAnimationsEquals(RawGeckoStyleAnimationListBorrowed,
                                  RawGeckoStyleAnimationListBorrowed);
+void Gecko_UpdateAnimations(RawGeckoElementBorrowed aElement,
+                            nsIAtom* aPseudoTagOrNull,
+                            ServoComputedValuesBorrowed aComputedValues,
+                            ServoComputedValuesBorrowedOrNull aParentComputedValues);
 
 // Atoms.
 nsIAtom* Gecko_Atomize(const char* aString, uint32_t aLength);

layout/style/ServoStyleSet.cpp

@@ -11,7 +11,6 @@
 #include "mozilla/dom/ChildIterator.h"
 #include "mozilla/dom/Element.h"
 #include "mozilla/dom/ElementInlines.h"
-#include "nsAnimationManager.h"
 #include "nsCSSAnonBoxes.h"
 #include "nsCSSPseudoElements.h"
 #include "nsHTMLStyleSheet.h"
@@ -164,33 +163,8 @@ ServoStyleSet::GetContext(already_AddRefed<ServoComputedValues> aComputedValues,
   // See bug 1344914.
   bool skipFixup = false;
 
-  RefPtr<nsStyleContext> result =
-    NS_NewStyleContext(aParentContext, mPresContext, aPseudoTag,
-                       aPseudoType, Move(aComputedValues), skipFixup);
-
-  // Ignore animations for print or print preview, and for elements
-  // that are not attached to the document tree.
-  if (mPresContext->IsDynamic() &&
-      aElementForAnimation &&
-      aElementForAnimation->IsInComposedDoc()) {
-    // Update/build CSS animations in the case where animation properties are
-    // changed.
-    // FIXME: Bug 1341985: This isn't right place to update CSS animations.
-    // We should do it in a SequentialTask and trigger the second traversal for
-    // the animation's restyle after the SequentialTask.
-    const ServoComputedValues* currentStyle =
-      result->StyleSource().AsServoComputedValues();
-    const ServoComputedValues* parentStyle =
-      result->GetParent()
-        ? result->GetParent()->StyleSource().AsServoComputedValues()
-        : nullptr;
-    mPresContext->AnimationManager()->UpdateAnimations(aElementForAnimation,
-                                                       aPseudoTag,
-                                                       currentStyle,
-                                                       parentStyle);
-  }
-
-  return result.forget();
+  return NS_NewStyleContext(aParentContext, mPresContext, aPseudoTag,
+                            aPseudoType, Move(aComputedValues), skipFixup);
 }
 
 void