context: add workingcommitctx for exact context to be committed Before this patch, "workingctx" is also used for the context to be committed. But "workingctx" works incorrectly in some cases. For example, even when only some of changed files in the working directory are committed, "status()" on "workingctx" object for committing recognizes files not to be committed as changed, too. As the preparation for fixing these issues, this patch chooses adding new class "workingcommitctx" for exact context to be committed, because switching by the flag (like "self._fixedstatus" or so) in some code paths of "workingctx" is less readable and maintenancable.

context: make unknown/ignored/clean of cached status empty for equivalence Before this patch, "workingctx.status" caches the result of "dirstate.status" directly into "self._status". But "dirstate.status" is invoked with False "list*" arguments in normal "self._status" accessing route, and this makes "unknown"/"ignored"/"clean" of status empty. This may cause unexpected result of code paths internally accessing to them (accessors for external usage are already removed by previous patch). This patch makes "unknown"/"ignored"/"clean" of cached status empty for equivalence. Making them empty is executed only when at least one of "unknown", "ignored" or "clean" has files, for efficiency.