Clean up the public interface of Map.

src/objects-inl.h

Index: src/objects-inl.h
diff --git a/src/objects-inl.h b/src/objects-inl.h
index 96c397f51bd22331614248c1baf9203316c6fbd7..c80bde53a005b583633cb1ae3e0b059ac0817c3c 100644
--- a/src/objects-inl.h
+++ b/src/objects-inl.h
@@ -5020,19 +5020,6 @@ uint32_t Map::bit_field3() {
 }
 
 
-void Map::ClearTransitions(Heap* heap, WriteBarrierMode mode) {
-  Object* back_pointer = GetBackPointer();
-
-  if (Heap::ShouldZapGarbage() && HasTransitionArray()) {
-    ZapTransitions();
-  }
-
-  WRITE_FIELD(this, kTransitionsOrBackPointerOffset, back_pointer);
-  CONDITIONAL_WRITE_BARRIER(
-      heap, this, kTransitionsOrBackPointerOffset, back_pointer, mode);
-}
-
-
 void Map::AppendDescriptor(Descriptor* desc) {
   DescriptorArray* descriptors = instance_descriptors();
   int number_of_own_descriptors = NumberOfOwnDescriptors();
@@ -5078,11 +5065,6 @@ bool Map::CanHaveMoreTransitions() {
 }
 
 
-void Map::SetTransition(int transition_index, Map* target) {
-  transitions()->SetTarget(transition_index, target);
-}
-
-
 Map* Map::GetTransition(int transition_index) {
   return transitions()->GetTarget(transition_index);
 }