Recursion limit for one-char string replace and retire String::kMinNonFlatLength.

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index d1d184da35c4bdb8020fe4bde4302d28cf778a53..c223de854db6ead1b5fc23452bfbbd342f85843d 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -6591,9 +6591,6 @@ class String: public HeapObject {
   static const unsigned kMaxAsciiCharCodeU = unibrow::Utf8::kMaxOneByteChar;
   static const int kMaxUC16CharCode = 0xffff;
 
-  // Minimum length for a cons string.
-  static const int kMinNonFlatLength = 13;
-
   // Mask constant for checking if a string has a computed hash code
   // and if it is an array index.  The least significant bit indicates
   // whether a hash code has been computed.  If the hash code has been