(gdb-source-file-list): Declare.

(gdb-source-file-list): Declare.
(gdbmi): Bind new functions.
(gdbmi-var-list-children-handler, gdbmi-var-list-children-regexp):
Handle string expressions properly.  Move "type" field into regexp.
(gdbmi-var-update-regexp, gdbmi-var-update-handler): Handle string
expressions properly.  Update speedbar.
(gdbmi-breakpoints-buffer, gdb-stack-buffer, gdb-locals-buffer)
(gdb-registers-buffer): Use def-gdb-auto-update-trigger instead of
def-gdb-auto-updated-buffer as handlers is defined explicitly.
(gdb-stack-list-locals-handler): Handle string expressions properly.
(gdb-data-list-register-values-handler)
(gdb-data-list-register-values-custom): Fontify buffer.