Arrow functions: Cleanup handling of the prototype property

The old code did not work correctly in case of optimizations. I
found this out when implementing concise methods and we now plumb
through the function kind so we know what kind of Map to create for
the function.

BUG=v8:2700
LOG=y
R=rossberg@chromium.org

Review URL: https://codereview.chromium.org/562253002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@23920 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
[turbofan] Use correct register_save_area_size with OOL constant pool.

Follow-up to r23843.

BUG=
R=mstarzinger@chromium.org

Review URL: https://codereview.chromium.org/565693002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@23921 ce2b1a6d-e550-0410-aec6-3dcde31c8c00