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

src/heap.cc

Index: src/heap.cc
diff --git a/src/heap.cc b/src/heap.cc
index a1f3260454bee04e223e9cbe750ffa59bdd90629..3c788781fb27dc5b604a2e8d5ea41efd29d49448 100644
--- a/src/heap.cc
+++ b/src/heap.cc
@@ -2948,9 +2948,9 @@ MaybeObject* Heap::AllocateConsString(String* first, String* second) {
   }
 
   // If the resulting string is small make a flat string.
-  if (length < String::kMinNonFlatLength) {
+  if (length < ConsString::kMinLength) {
     // Note that neither of the two inputs can be a slice because:
-    STATIC_ASSERT(String::kMinNonFlatLength <= SlicedString::kMinLength);
+    STATIC_ASSERT(ConsString::kMinLength <= SlicedString::kMinLength);
     ASSERT(first->IsFlat());
     ASSERT(second->IsFlat());
     if (is_ascii) {