(init_buffer_once): Init top_line_format.

(init_buffer_once): Init top_line_format.
(default-top-line-format): New.
(top-line-format): New buffer-local variable.
(init_buffer_once): Set buffer_local_flags for
scroll_*_aggressively.
(syms_of_buffer): Add DEFVAR_PER_BUFFER for scroll-*-aggressively.
(init_buffer_once): Set defaults for these variables.
(syms_of_buffer): Add default-scroll-*-aggressively.
(indicate-empty-lines): New.
(default-indicate-zv-lines): Likewise.
(init_buffer_once): Add default for `indicate-zv-lines'.
(init_buffer_once): New variable `default-indicate-zv-lines'.
(syms_of_buffer): New buffer-local varianle `indicate-zv-lines'.
(init_buffer_once): Add left_margin_width and
right_margin_width to buffer_local_flags.
(syms_of_buffer): Add buffer-local variables
left-margin-width and right-margin-width.  Add defaults
default-left-margin-width and default-right-margin-width.
(record_buffer): Return void.
(record_asynch_buffer_change): Return void.
(Fget_buffer_create): Initialize minibuffer_prompt_length.
(Fmake_indirect_buffer): Ditto.
(Fkill_buffer): Ditto.