1 files changed, 16 insertions, 9 deletions

diff --git a/dom/base/nsDocument.cpp b/dom/base/nsDocument.cpp
index a6ed419df..6b8e11db0 100644
--- a/dom/base/nsDocument.cpp
+++ b/dom/base/nsDocument.cpp
@@ -9222,19 +9222,23 @@ already_AddRefed<nsIURI>
 nsDocument::ResolvePreloadImage(nsIURI *aBaseURI,
                                 const nsAString& aSrcAttr,
                                 const nsAString& aSrcsetAttr,
-                                const nsAString& aSizesAttr)
+                                const nsAString& aSizesAttr,
+                                bool *aIsImgSet)
 {
   nsString sourceURL;
+  bool isImgSet;
   if (mPreloadPictureDepth == 1 && !mPreloadPictureFoundSource.IsVoid()) {
     // We're in a <picture> element and found a URI from a source previous to
     // this image, use it.
     sourceURL = mPreloadPictureFoundSource;
+    isImgSet = true;
   } else {
     // Otherwise try to use this <img> as a source
     HTMLImageElement::SelectSourceForTagWithAttrs(this, false, aSrcAttr,
                                                   aSrcsetAttr, aSizesAttr,
                                                   NullString(), NullString(),
                                                   sourceURL);
+    isImgSet = !aSrcsetAttr.IsEmpty();
   }
 
   // Empty sources are not loaded by <img> (i.e. not resolved to the baseURI)
@@ -9252,6 +9256,8 @@ nsDocument::ResolvePreloadImage(nsIURI *aBaseURI,
     return nullptr;
   }
 
+  *aIsImgSet = isImgSet;
+
   // We don't clear mPreloadPictureFoundSource because subsequent <img> tags in
   // this this <picture> share the same <sources> (though this is not valid per
   // spec)
@@ -9260,16 +9266,12 @@ nsDocument::ResolvePreloadImage(nsIURI *aBaseURI,
 
 void
 nsDocument::MaybePreLoadImage(nsIURI* uri, const nsAString &aCrossOriginAttr,
-                              ReferrerPolicy aReferrerPolicy)
+                              ReferrerPolicy aReferrerPolicy, bool aIsImgSet)
 {
   // Early exit if the img is already present in the img-cache
   // which indicates that the "real" load has already started and
   // that we shouldn't preload it.
-  int16_t blockingStatus;
-  if (nsContentUtils::IsImageInCache(uri, static_cast<nsIDocument *>(this)) ||
-      !nsContentUtils::CanLoadImage(uri, static_cast<nsIDocument *>(this),
-                                    this, NodePrincipal(), &blockingStatus,
-                                    nsIContentPolicy::TYPE_INTERNAL_IMAGE_PRELOAD)) {
+  if (nsContentUtils::IsImageInCache(uri, static_cast<nsIDocument *>(this))) {
     return;
   }
 
@@ -9288,6 +9290,10 @@ nsDocument::MaybePreLoadImage(nsIURI* uri, const nsAString &aCrossOriginAttr,
     MOZ_CRASH("Unknown CORS mode!");
   }
 
+  nsContentPolicyType policyType =
+    aIsImgSet ? nsIContentPolicy::TYPE_IMAGESET :
+                nsIContentPolicy::TYPE_INTERNAL_IMAGE_PRELOAD;
+
   // Image not in cache - trigger preload
   RefPtr<imgRequestProxy> request;
   nsresult rv =
@@ -9301,7 +9307,7 @@ nsDocument::MaybePreLoadImage(nsIURI* uri, const nsAString &aCrossOriginAttr,
                               loadFlags,
                               NS_LITERAL_STRING("img"),
                               getter_AddRefs(request),
-                              nsIContentPolicy::TYPE_INTERNAL_IMAGE_PRELOAD);
+                              policyType);
 
   // Pin image-reference to avoid evicting it from the img-cache before
   // the "real" load occurs. Unpinned in DispatchContentLoadedEvents and
@@ -11943,7 +11949,8 @@ nsIDocument::DocAddSizeOfExcludingThis(nsWindowSizes* aWindowSizes) const
                                        &aWindowSizes->mLayoutPresShellSize,
                                        &aWindowSizes->mLayoutStyleSetsSize,
                                        &aWindowSizes->mLayoutTextRunsSize,
-                                       &aWindowSizes->mLayoutPresContextSize);
+                                       &aWindowSizes->mLayoutPresContextSize,
+                                       &aWindowSizes->mLayoutFramePropertiesSize);
   }
 
   aWindowSizes->mPropertyTablesSize +=