Bug 1552911 - Tweak the internal C++ constructor of ResizeObserverEntry to require aBorderBoxSize and aContentBoxSize. r=dholbert

Differential Revision: https://phabricator.services.mozilla.com/D32031

--HG--
extra : moz-landing-system : lando

dom/base/ResizeObserver.cpp

@@ -220,15 +220,13 @@ uint32_t ResizeObserver::BroadcastActiveObservations() {
 
   for (auto& observation : mActiveTargets) {
     Element* target = observation->Target();
-    RefPtr<ResizeObserverEntry> entry = new ResizeObserverEntry(this, *target);
 
     nsSize borderBoxSize =
         GetTargetSize(target, ResizeObserverBoxOptions::Border_box);
-    entry->SetBorderBoxSize(borderBoxSize);
-
     nsSize contentBoxSize =
         GetTargetSize(target, ResizeObserverBoxOptions::Content_box);
-    entry->SetContentRectAndSize(contentBoxSize);
+    RefPtr<ResizeObserverEntry> entry =
+        new ResizeObserverEntry(this, *target, borderBoxSize, contentBoxSize);
 
     if (!entries.AppendElement(entry.forget(), fallible)) {
       // Out of memory.

dom/base/ResizeObserver.h

@@ -175,10 +175,15 @@ class ResizeObserverEntry final : public nsISupports, public nsWrapperCache {
   NS_DECL_CYCLE_COLLECTING_ISUPPORTS
   NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS(ResizeObserverEntry)
 
-  ResizeObserverEntry(nsISupports* aOwner, Element& aTarget)
+  ResizeObserverEntry(nsISupports* aOwner, Element& aTarget,
+                      const nsSize& aBorderBoxSize,
+                      const nsSize& aContentBoxSize)
       : mOwner(aOwner), mTarget(&aTarget) {
     MOZ_ASSERT(mOwner, "Need a non-null owner");
     MOZ_ASSERT(mTarget, "Need a non-null target element");
+
+    SetBorderBoxSize(aBorderBoxSize);
+    SetContentRectAndSize(aContentBoxSize);
   }
 
   nsISupports* GetParentObject() const { return mOwner; }
@@ -203,14 +208,14 @@ class ResizeObserverEntry final : public nsISupports, public nsWrapperCache {
   ResizeObserverSize* BorderBoxSize() const { return mBorderBoxSize; }
   ResizeObserverSize* ContentBoxSize() const { return mContentBoxSize; }
 
+ private:
+  ~ResizeObserverEntry() = default;
+
   // Set borderBoxSize.
   void SetBorderBoxSize(const nsSize& aSize);
   // Set contentRect and contentBoxSize.
   void SetContentRectAndSize(const nsSize& aSize);
 
- protected:
-  ~ResizeObserverEntry() = default;
-
   nsCOMPtr<nsISupports> mOwner;
   nsCOMPtr<Element> mTarget;