--- a/layout/svg/nsSVGEffects.cpp
+++ b/layout/svg/nsSVGEffects.cpp
@@ -470,18 +470,16 @@ GetEffectProperty(nsIURI *aURI, nsIFrame
     return nullptr;
 
   FrameProperties props = aFrame->Properties();
   nsSVGRenderingObserver *prop =
     static_cast<nsSVGRenderingObserver*>(props.Get(aProperty));
   if (prop)
     return prop;
   prop = aCreate(aURI, aFrame, false);
-  if (!prop)
-    return nullptr;
   NS_ADDREF(prop);
   props.Set(aProperty, static_cast<nsISupports*>(prop));
   return prop;
 }
 
 static nsSVGFilterProperty*
 GetOrCreateFilterProperty(nsIFrame *aFrame)
 {
@@ -489,18 +487,16 @@ GetOrCreateFilterProperty(nsIFrame *aFra
   if (!effects->HasFilters())
     return nullptr;
 
   FrameProperties props = aFrame->Properties();
   nsSVGFilterProperty *prop = props.Get(nsSVGEffects::FilterProperty());
   if (prop)
     return prop;
   prop = new nsSVGFilterProperty(effects->mFilters, aFrame);
-  if (!prop)
-    return nullptr;
   NS_ADDREF(prop);
   props.Set(nsSVGEffects::FilterProperty(), prop);
   return prop;
 }
 
 static nsSVGMaskProperty*
 GetOrCreateMaskProperty(nsIFrame *aFrame)
 {

--- a/layout/svg/nsSVGEffects.h
+++ b/layout/svg/nsSVGEffects.h
@@ -38,17 +38,18 @@ class nsSVGFilterChainObserver;
  *
  * Concrete implementations of this interface need to implement
  * "GetTarget()" to specify the piece of SVG content that they'd like to
  * monitor, and they need to implement "DoUpdate" to specify how we'll react
  * when that content gets re-rendered. They also need to implement a
  * constructor and destructor, which should call StartListening and
  * StopListening, respectively.
  */
-class nsSVGRenderingObserver : public nsStubMutationObserver {
+class nsSVGRenderingObserver : public nsStubMutationObserver
+{
 
 protected:
   virtual ~nsSVGRenderingObserver()
     {}
 
 public:
   typedef mozilla::dom::Element Element;
   nsSVGRenderingObserver()
@@ -103,30 +104,32 @@ protected:
  * track when those resources change and when the DOM changes in ways
  * that affect which element is referenced by a given ID (e.g., when
  * element IDs change). The code here is responsible for that.
  *
  * When a frame references a supporting resource, we create a property
  * object derived from nsSVGIDRenderingObserver to manage the relationship. The
  * property object is attached to the referencing frame.
  */
-class nsSVGIDRenderingObserver : public nsSVGRenderingObserver {
+class nsSVGIDRenderingObserver : public nsSVGRenderingObserver
+{
 public:
   typedef mozilla::dom::Element Element;
   nsSVGIDRenderingObserver(nsIURI* aURI, nsIContent* aObservingContent,
                          bool aReferenceImage);
   virtual ~nsSVGIDRenderingObserver();
 
 protected:
   Element* GetTarget() override { return mElement.get(); }
 
   // This is called when the referenced resource changes.
   virtual void DoUpdate() override;
 
-  class SourceReference : public nsReferencedElement {
+  class SourceReference : public nsReferencedElement
+  {
   public:
     explicit SourceReference(nsSVGIDRenderingObserver* aContainer) : mContainer(aContainer) {}
   protected:
     virtual void ElementChanged(Element* aFrom, Element* aTo) override {
       mContainer->StopListening();
       nsReferencedElement::ElementChanged(aFrom, aTo);
       mContainer->StartListening();
       mContainer->DoUpdate();
@@ -164,17 +167,18 @@ private:
   // the presshell for the frames we care about and, before we use the frame,
   // we test the presshell to see if it's destroying itself. If it is,
   // then the frame pointer is not valid and we know the frame has gone away.
   // mFramePresShell may be null, but when mFrame is non-null, mFramePresShell
   // is guaranteed to be non-null, too.
   nsIPresShell *mFramePresShell;
 };
 
-class nsSVGRenderingObserverProperty : public nsSVGIDRenderingObserver {
+class nsSVGRenderingObserverProperty : public nsSVGIDRenderingObserver
+{
 public:
   NS_DECL_ISUPPORTS
 
   nsSVGRenderingObserverProperty(nsIURI* aURI, nsIFrame *aFrame,
                                  bool aReferenceImage)
     : nsSVGIDRenderingObserver(aURI, aFrame->GetContent(), aReferenceImage)
     , mFrameReference(aFrame)
   {}
@@ -195,17 +199,18 @@ protected:
  * e.g. url(#svg-filter-1)
  *
  * It fires invalidations when the SVG filter element's id changes or when
  * the SVG filter element's content changes.
  *
  * The nsSVGFilterChainObserver class manages a list of nsSVGFilterReferences.
  */
 class nsSVGFilterReference final : public nsSVGIDRenderingObserver
-                                 , public nsISVGFilterReference {
+                                 , public nsISVGFilterReference
+{
 public:
   nsSVGFilterReference(nsIURI* aURI,
                        nsIContent* aObservingContent,
                        nsSVGFilterChainObserver* aFilterChainObserver)
     : nsSVGIDRenderingObserver(aURI, aObservingContent, false)
     , mFilterChainObserver(aFilterChainObserver)
   {
   }
@@ -241,17 +246,18 @@ private:
  * reference filters in a filter chain.
  * e.g. filter: url(#svg-filter-1) blur(10px) url(#svg-filter-2);
  *
  * In the above example, the nsSVGFilterChainObserver will manage two
  * nsSVGFilterReferences, one for each SVG reference filter. CSS filters like
  * "blur(10px)" don't reference filter elements, so they don't need an
  * nsSVGFilterReference. The style system invalidates changes to CSS filters.
  */
-class nsSVGFilterChainObserver : public nsISupports {
+class nsSVGFilterChainObserver : public nsISupports
+{
 public:
   nsSVGFilterChainObserver(const nsTArray<nsStyleFilter>& aFilters,
                            nsIContent* aFilteredElement);
 
   bool ReferencesValidResources();
   bool IsInObserverLists() const;
   void Invalidate() { DoUpdate(); }
 
@@ -263,42 +269,45 @@ protected:
   virtual ~nsSVGFilterChainObserver();
 
   virtual void DoUpdate() = 0;
 
 private:
   nsTArray<RefPtr<nsSVGFilterReference>> mReferences;
 };
 
-class nsSVGFilterProperty : public nsSVGFilterChainObserver {
+class nsSVGFilterProperty : public nsSVGFilterChainObserver
+{
 public:
   nsSVGFilterProperty(const nsTArray<nsStyleFilter> &aFilters,
                       nsIFrame *aFilteredFrame)
     : nsSVGFilterChainObserver(aFilters, aFilteredFrame->GetContent())
     , mFrameReference(aFilteredFrame)
   {}
 
   void DetachFromFrame() { mFrameReference.Detach(); }
 
 protected:
   virtual void DoUpdate() override;
 
   nsSVGFrameReferenceFromProperty mFrameReference;
 };
 
-class nsSVGMarkerProperty final : public nsSVGRenderingObserverProperty {
+class nsSVGMarkerProperty final: public nsSVGRenderingObserverProperty
+{
 public:
   nsSVGMarkerProperty(nsIURI *aURI, nsIFrame *aFrame, bool aReferenceImage)
     : nsSVGRenderingObserverProperty(aURI, aFrame, aReferenceImage) {}
 
 protected:
   virtual void DoUpdate() override;
 };
 
-class nsSVGTextPathProperty final : public nsSVGRenderingObserverProperty {
+class nsSVGTextPathProperty final : public nsSVGRenderingObserverProperty
+{
 public:
   nsSVGTextPathProperty(nsIURI *aURI, nsIFrame *aFrame, bool aReferenceImage)
     : nsSVGRenderingObserverProperty(aURI, aFrame, aReferenceImage)
     , mValid(true) {}
 
   virtual bool ObservesReflow() override { return false; }
 
 protected:
@@ -308,17 +317,18 @@ private:
   /**
    * Returns true if the target of the textPath is the frame of a 'path' element.
    */
   bool TargetIsValid();
 
   bool mValid;
 };
 
-class nsSVGPaintingProperty final : public nsSVGRenderingObserverProperty {
+class nsSVGPaintingProperty final : public nsSVGRenderingObserverProperty
+{
 public:
   nsSVGPaintingProperty(nsIURI *aURI, nsIFrame *aFrame, bool aReferenceImage)
     : nsSVGRenderingObserverProperty(aURI, aFrame, aReferenceImage) {}
 
 protected:
   virtual void DoUpdate() override;
 };
 
@@ -351,17 +361,18 @@ private:
  * is needed, and then at paint time the observer will do a clean lookup
  * of the referenced element and [re-]add itself to the element's observer list.
  *
  * InvalidateAll must be called before this object is destroyed, i.e.
  * before the referenced frame is destroyed. This should normally happen
  * via nsSVGContainerFrame::RemoveFrame, since only frames in the frame
  * tree should be referenced.
  */
-class nsSVGRenderingObserverList {
+class nsSVGRenderingObserverList
+{
 public:
   nsSVGRenderingObserverList()
     : mObservers(4)
   {
     MOZ_COUNT_CTOR(nsSVGRenderingObserverList);
   }
 
   ~nsSVGRenderingObserverList() {
@@ -397,17 +408,18 @@ public:
    * to them.
    */
   void RemoveAll();
 
 private:
   nsTHashtable<nsPtrHashKey<nsSVGRenderingObserver> > mObservers;
 };
 
-class nsSVGEffects {
+class nsSVGEffects
+{
 public:
   typedef mozilla::dom::Element Element;
   typedef nsInterfaceHashtable<nsURIHashKey, nsIMutationObserver>
     URIObserverHashtable;
 
   using ObserverPropertyDescriptor =
     const mozilla::FramePropertyDescriptor<nsISupports>*;
   using URIObserverHashtablePropertyDescriptor =