Remove the obsolete Code::IsPregenerated flag.

src/objects-inl.h

Index: src/objects-inl.h
diff --git a/src/objects-inl.h b/src/objects-inl.h
index ee81c2fcbde610dcddf27d8d3812c3cf20b8ed28..1717a5f4b59a8cba4db473b0e0634e9c9c437b93 100644
--- a/src/objects-inl.h
+++ b/src/objects-inl.h
@@ -3959,19 +3959,6 @@ bool Code::has_major_key() {
 }
 
 
-bool Code::is_pregenerated() {
-  return (kind() == STUB && IsPregeneratedField::decode(flags()));
-}
-
-
-void Code::set_is_pregenerated(bool value) {
-  ASSERT(kind() == STUB);
-  Flags f = flags();
-  f = static_cast<Flags>(IsPregeneratedField::update(f, value));
-  set_flags(f);
-}
-
-
 bool Code::optimizable() {
   ASSERT_EQ(FUNCTION, kind());
   return READ_BYTE_FIELD(this, kOptimizableOffset) == 1;