Make a backport branch for r1574868.

git-svn-id: https://svn.apache.org/repos/asf/subversion/branches/1.7.x-r1574868@1575332 13f79535-47bb-0310-9956-ffa450edef68
On the 1.7.x-r1574868 branch: merge r1574868 from trunk.

git-svn-id: https://svn.apache.org/repos/asf/subversion/branches/1.7.x-r1574868@1575333 13f79535-47bb-0310-9956-ffa450edef68
Create 1.7 backport branch for r1641564.

git-svn-id: https://svn.apache.org/repos/asf/subversion/branches/1.7.x-r1641564@1641574 13f79535-47bb-0310-9956-ffa450edef68
Merge r1641564 and drop change to externals_tests.py as the
modified test is not on the branch.


git-svn-id: https://svn.apache.org/repos/asf/subversion/branches/1.7.x-r1641564@1641578 13f79535-47bb-0310-9956-ffa450edef68
Merge the 1.7.x-r1574868 branch:

 * r1574868
   Don't let invalid mergeinfo stop 'svnadmin dump' from producing a dump.
     Part of issue #4476 "Mergeinfo containing r0 makes svnsync and svnadmin
     dump fail".
   Justification:
     A formatting error in what is essentially client-side metadata, albeit
     with repository-side interpretation as well, should never prevent
     dumping the repository. This issue only occurs when svnadmin is trying
     to warn us of mergeinfo revisions that might be unexpected, so it is
     not essential.
   Notes:
     There is a work-around, at least in theory: a dump starting from
     revision 0 or 1 does not suffer from this problem.
   Branch:
     ^/subversion/branches/1.7.x-r1574868
   Votes:
     +1: julianfoad, rhuijben, stefan2


git-svn-id: https://svn.apache.org/repos/asf/subversion/branches/1.7.x@1642629 13f79535-47bb-0310-9956-ffa450edef68
Merge the 1.7.x-r1641564 branch:

 * r1641564
   Fix issue 4185: file external not following history.
   Justification:
     Checkout/update fails, regression from 1.6.
   Notes:
     Failure was silent, notification occurred but file was not present in wc.
   Branch:
     ^/subversion/branches/1.7.x-r1641564
   Votes:
     +1: philip, rhuijben, stefan2


git-svn-id: https://svn.apache.org/repos/asf/subversion/branches/1.7.x@1642631 13f79535-47bb-0310-9956-ffa450edef68