diff --git a/gfx/2d/HelpersCairo.h b/gfx/2d/HelpersCairo.h
index b844f2cfdf..53e9163c54 100644
--- a/gfx/2d/HelpersCairo.h
+++ b/gfx/2d/HelpersCairo.h
@@ -152,10 +152,8 @@ GfxFormatToCairoFormat(SurfaceFormat format)
   switch (format)
   {
     case SurfaceFormat::A8R8G8B8_UINT32:
-    case SurfaceFormat::B8G8R8A8: // XXX?
       return CAIRO_FORMAT_ARGB32;
     case SurfaceFormat::X8R8G8B8_UINT32:
-    case SurfaceFormat::B8G8R8X8: // XXX?
       return CAIRO_FORMAT_RGB24;
     case SurfaceFormat::A8:
       return CAIRO_FORMAT_A8;
diff --git a/gfx/2d/Types.h b/gfx/2d/Types.h
index 36dc34297f..015757d72d 100644
--- a/gfx/2d/Types.h
+++ b/gfx/2d/Types.h
@@ -61,10 +61,10 @@ enum class SurfaceFormat : int8_t {
   // The following values are endian-independent synonyms. The _UINT32 suffix
   // indicates that the name reflects the layout when viewed as a uint32_t
   // value.
-#if MOZ_LITTLE_ENDIAN
+#if MOZ_BIG_ENDIAN
   A8R8G8B8_UINT32 = B8G8R8A8,       // 0xAARRGGBB
   X8R8G8B8_UINT32 = B8G8R8X8        // 0x00RRGGBB
-#elif MOZ_BIG_ENDIAN
+#elif MOZ_LITTLE_ENDIAN
   A8R8G8B8_UINT32 = A8R8G8B8,       // 0xAARRGGBB
   X8R8G8B8_UINT32 = X8R8G8B8        // 0x00RRGGBB
 #else