PropertyListNode::emitNode duplicates the code to put a constant property

PropertyListNode::emitNode duplicates the code to put a constant property
https://bugs.webkit.org/show_bug.cgi?id=140761

Reviewed by Geoffrey Garen.

Extracted PropertyListNode::emitPutConstantProperty to share the code.

Also made PropertyListNode::emitBytecode private since nobody is calling this function directly.

* bytecompiler/NodesCodegen.cpp:
(JSC::PropertyListNode::emitBytecode):
(JSC::PropertyListNode::emitPutConstantProperty): Added.
* parser/Nodes.h:

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@178918 268f45cc-cd09-0410-ab3c-d52691b4dbfc