From: Teodor Zlatanov <tzz@lifelogs.com>

From: Teodor Zlatanov  <tzz@lifelogs.com>
(compilation-start): Set next-error-last-buffer so
next-error knows where to jump.
(compilation-setup): Set the buffer-local variable
next-error-function to 'compilation-next-error-function.
(compilation-buffer-p, compilation-buffer-internal-p): Use an
alternate way to find if a buffer is a compilation buffer, for
next-error convenience.
(next-error-no-select, previous-error-no-select, next-error)
(previous-error, first-error): Move to simple.el.
(compilation-find-buffer): Move to next-error-find-buffer in simple.el.
(compilation-last-buffer): Remove.
(compilation-start, compilation-next-error, compilation-setup)
(compilation-next-error-function, compilation-find-buffer):
Remove compilation-last-buffer use.