bookmarks: Avoid unconditional forwarding of bookmarks for the null revision
This patch fixes the following minor problem:
% hg bookmark -r null test
% hg bookmarks
test -1:000000000000
[...]
% hg commit
% hg bookmarks
* test 17:861ce7a241f9
That is: Bookmarks referring to the null revision are always forwarded
to the current revision.
% test file addition with bad case
adding a
A a
a
% test case collision on rename (issue 750)
adding a
a
committed changeset 0:07f4944404050f47db2e5c5071e0e84e7a27bba9
A: not overwriting - file exists
% test case collision between revisions (issue 912)
adding a
adding A
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
1 files updated, 0 files merged, 1 files removed, 0 files unresolved