Give the constant 1024*1024 introduced in an earlier commit a name, "batch_memory_max", and move it from view.cc to view_builder.hh. It now resides next to the pre-existing constant that controlled how many rows were read in each build step, "batch_size". Signed-off-by: Nadav Har'El <nyh@scylladb.com> Message-Id: <20190217100222.15673-1-nyh@scylladb.com>