BIND 10 #507: Empty node processing: In-memory data source changes

[BIND 10 Development]

#507: Empty node processing: In-memory data source changes
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                 Reporter:  stephen  |                Owner:  jinmei
                     Type:           |               Status:  assigned
  enhancement                        |            Milestone:  A-Team-
                 Priority:  major    |  Sprint-20110209
                Component:  data     |           Resolution:
  source                             |            Sensitive:  0
                 Keywords:           |  Add Hours to Ticket:  0
Estimated Number of Hours:  8.0      |          Total Hours:  0
                Billable?:  1        |
                Internal?:  0        |
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Comment (by jinmei):

 trac507 is ready for review.

 While thinking about how to test this, I realized we actually didn't need
 richer features implemented in #517 for the empty node handling.  We only
 need to have the "empty data OK" mode and the ability to exchange the
 information on the "last comparison" in RBTree::find().

 So I decided to complete this task rather than waiting for the completion
 of #517.  I started with incorporating necessary changes from #517
 into the trac507 branch.  The incorporated part has already been reviewed
 in trac #517, so the review for this ticket can start from the next
 commit: git diff 1ab958cdc6f1ebdbf88f863a4a15d6a5783035bc

 Some part of the RBTreeNodeChain class haven't been merged to this branch
 (that part hasn't been fully reviewed and is actually not necessary for
 this task), but some comments for the unimplemented part was intentionally
 left (with some notes that they are not yet implemented), assuming #517
 will soon be merged anyway.

-- 
Ticket URL: <http://bind10.isc.org/ticket/507#comment:2>
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