Incremental updating of inline summaries.

Incremental updating of inline summaries.

        * ipa-fnsummary.c (ipa_fn_summary::account_size_time): Allow
	negative time in calls summary; correct roundoff errors
	leading to negative times.
	(ipa_merge_fn_summary_after_inlining): Update calls size time table
	if present.
	(ipa_update_overall_fn_summary): Add RESET parameter.
	* ipa-fnsummary.h (ipa_update_overall_fn_summary): Update prototype.
	* ipa-inline-transform.c (inline_call): Enable incremental updates.

From-SVN: r278541