diff --git a/layout/style/nsStyleStruct.cpp b/layout/style/nsStyleStruct.cpp
index 904ff53480bf..da0e3986430f 100644
--- a/layout/style/nsStyleStruct.cpp
+++ b/layout/style/nsStyleStruct.cpp
@@ -2195,7 +2195,7 @@ nsStyleImage::ComputeActualCropRect(nsIntRect& aActualCropRect,
 nsresult
 nsStyleImage::StartDecoding() const
 {
-  if ((mType == eStyleImageType_Image) && mImage) {
+  if (mType == eStyleImageType_Image) {
     return mImage->StartDecoding();
   }
   return NS_OK;
diff --git a/layout/style/nsStyleStruct.h b/layout/style/nsStyleStruct.h
index 0ad6fd9a68e7..38ce2dc8b727 100644
--- a/layout/style/nsStyleStruct.h
+++ b/layout/style/nsStyleStruct.h
@@ -365,6 +365,7 @@ struct nsStyleImage
   }
   imgRequestProxy* GetImageData() const {
     MOZ_ASSERT(mType == eStyleImageType_Image, "Data is not an image!");
+    MOZ_ASSERT(mImage);
     MOZ_ASSERT(mImageTracked,
                "Should be tracking any image we're going to use!");
     return mImage;