diff --git a/gfx/thebes/gfxPlatformFontList.cpp b/gfx/thebes/gfxPlatformFontList.cpp
index 06da75ee49..e12f4e1975 100644
--- a/gfx/thebes/gfxPlatformFontList.cpp
+++ b/gfx/thebes/gfxPlatformFontList.cpp
@@ -901,7 +901,7 @@ gfxPlatformFontList::ResolveEmojiFontNames(
 void
 gfxPlatformFontList::GetFontFamiliesFromGenericFamilies(
     nsTArray<nsString>& aGenericNameFamilies,
-    nsAtom* aLangGroup,
+    nsIAtom* aLangGroup,
     nsTArray<RefPtr<gfxFontFamily>>* aGenericFamilies)
 {
     // lookup and add platform fonts uniquely
@@ -910,8 +910,7 @@ gfxPlatformFontList::GetFontFamiliesFromGenericFamilies(
         style.language = aLangGroup;
         style.systemFont = false;
         AutoTArray<gfxFontFamily*,10> families;
-        FindAndAddFamilies(genericFamily, &families, FindFamiliesFlags(0),
-                           &style);
+        FindAndAddFamilies(genericFamily, &families, &style, 1.0);
         for (gfxFontFamily* f : families) {
             if (!aGenericFamilies->Contains(f)) {
                 aGenericFamilies->AppendElement(f);
diff --git a/gfx/thebes/gfxPlatformFontList.h b/gfx/thebes/gfxPlatformFontList.h
index c3795a072a..d77c120593 100644
--- a/gfx/thebes/gfxPlatformFontList.h
+++ b/gfx/thebes/gfxPlatformFontList.h
@@ -386,7 +386,7 @@ protected:
     void
     GetFontFamiliesFromGenericFamilies(
         nsTArray<nsString>& aGenericFamilies,
-        nsAtom* aLangGroup,
+        nsIAtom* aLangGroup,
         nsTArray<RefPtr<gfxFontFamily>>* aFontFamilies);
 
     virtual nsresult InitFontListForPlatform() = 0;