add flag for future skia CL

see https://skia-review.googlesource.com/c/6206/

BUG=
NOTRY=True

Review-Url: https://codereview.chromium.org/2583023003
Cr-Commit-Position: refs/heads/master@{#439521}

skia/config/SkUserConfig.h

@@ -246,6 +246,10 @@ SK_API void SkDebugf_FileLine(const char* file, int line, bool fatal,
 #   define SK_USE_LEGACY_DISTANCE_FIELDS
 #endif
 
+#ifndef    SK_SUPPORT_LEGACY_CLIPOP_EXOTIC_NAMES
+#   define SK_SUPPORT_LEGACY_CLIPOP_EXOTIC_NAMES
+#endif
+
 ///////////////////////// Imported from BUILD.gn and skia_common.gypi
 
 /* In some places Skia can use static initializers for global initialization,