Bug 1334735 - Part 2: Add separate flag to track need to flush throttled animations. r=bz,birtles

MozReview-Commit-ID: 6Vi3laKcbmG

dom/animation/EffectCompositor.cpp

@@ -264,7 +264,7 @@ EffectCompositor::RequestRestyle(dom::Element* aElement,
     if (!elementsToRestyle.Contains(key)) {
       elementsToRestyle.Put(key, false);
     }
-    mPresContext->PresShell()->SetNeedStyleFlush();
+    mPresContext->PresShell()->SetNeedThrottledAnimationFlush();
   } else {
     // Get() returns 0 if the element is not found. It will also return
     // false if the element is found but does not have a pending restyle.

layout/base/PresShell.cpp

@@ -798,6 +798,7 @@ nsIPresShell::nsIPresShell()
     , mScrollPositionClampingScrollPortSizeSet(false)
     , mNeedLayoutFlush(true)
     , mNeedStyleFlush(true)
+    , mNeedThrottledAnimationFlush(true)
     , mPresShellId(0)
     , mFontSizeInflationEmPerLine(0)
     , mFontSizeInflationMinTwips(0)
@@ -4120,6 +4121,8 @@ PresShell::FlushPendingNotifications(mozilla::ChangesToFlush aFlush)
   mInFlush = true;
 
   mNeedStyleFlush = false;
+  mNeedThrottledAnimationFlush =
+    mNeedThrottledAnimationFlush && !aFlush.mFlushAnimations;
   mNeedLayoutFlush =
     mNeedLayoutFlush && (flushType < FlushType::InterruptibleLayout);
 
@@ -4247,6 +4250,9 @@ PresShell::FlushPendingNotifications(mozilla::ChangesToFlush aFlush)
 
   if (!didStyleFlush && flushType >= FlushType::Style && !mIsDestroying) {
     SetNeedStyleFlush();
+    if (aFlush.mFlushAnimations) {
+      SetNeedThrottledAnimationFlush();
+    }
   }
 
   if (!didLayoutFlush && !mIsDestroying &&

layout/base/nsIPresShell.h

@@ -590,24 +590,27 @@ public:
    * function returns false, we definitely don't need to flush.
    *
    * @param aFlushType The flush type to check.  This must be
-   *   >= FlushType::Style.
+   *   >= FlushType::Style.  This also returns true if a throttled
+   *   animation flush is required.
    */
   bool NeedFlush(mozilla::FlushType aType) const
   {
     // We check mInFlush to handle re-entrant calls to FlushPendingNotifications
     // by reporting that we always need a flush in that case.  Otherwise,
-    // we could end up missing needed flushes, since we clear mNeedStyleFlush
-    // and mNeedLayoutFlush at the top of FlushPendingNotifications.
+    // we could end up missing needed flushes, since we clear the mNeedXXXFlush
+    // flags at the top of FlushPendingNotifications.
     MOZ_ASSERT(aType >= mozilla::FlushType::Style);
     return mNeedStyleFlush ||
            (mNeedLayoutFlush &&
             aType >= mozilla::FlushType::InterruptibleLayout) ||
            aType >= mozilla::FlushType::Display ||
+           mNeedThrottledAnimationFlush ||
            mInFlush;
   }
 
   inline void SetNeedStyleFlush();
   inline void SetNeedLayoutFlush();
+  inline void SetNeedThrottledAnimationFlush();
 
   bool NeedStyleFlush() { return mNeedStyleFlush; }
 
@@ -1837,6 +1840,10 @@ protected:
   // True if a style flush might not be a no-op
   bool mNeedStyleFlush : 1;
 
+  // True if there are throttled animations that would be processed when
+  // performing a flush with mFlushAnimations == true.
+  bool mNeedThrottledAnimationFlush : 1;
+
   uint32_t                  mPresShellId;
 
   // List of subtrees rooted at style scope roots that need to be restyled.

layout/base/nsIPresShellInlines.h

@@ -25,4 +25,15 @@ nsIPresShell::SetNeedStyleFlush()
   }
 }
 
+void
+nsIPresShell::SetNeedThrottledAnimationFlush()
+{
+  mNeedThrottledAnimationFlush = true;
+  if (nsIDocument* doc = mDocument->GetDisplayDocument()) {
+    if (nsIPresShell* shell = doc->GetShell()) {
+      shell->mNeedThrottledAnimationFlush = true;
+    }
+  }
+}
+
 #endif // nsIPresShellInlines_h