--- a/gfx/layers/Compositor.h
+++ b/gfx/layers/Compositor.h
@@ -190,16 +190,18 @@ protected:
 public:
   NS_INLINE_DECL_REFCOUNTING(Compositor)
 
   explicit Compositor(widget::CompositorWidgetProxy* aWidget,
                       CompositorBridgeParent* aParent = nullptr)
     : mCompositorID(0)
     , mDiagnosticTypes(DiagnosticTypes::NO_DIAGNOSTIC)
     , mParent(aParent)
+    , mPixelsPerFrame(0)
+    , mPixelsFilled(0)
     , mScreenRotation(ROTATION_0)
     , mWidget(aWidget)
   {
   }
 
   virtual already_AddRefed<DataTextureSource> CreateDataTextureSource(TextureFlags aFlags = TextureFlags::NO_FLAGS) = 0;
 
   virtual already_AddRefed<DataTextureSource>