* Add a method * change some uses of NH.getNode() in a bool context to use !NH.isNull() * Fix a bunch of places where we depended on the (undefined) order of   evaluation of arguments to function calls to ensure that getNode() was   called before getOffset().  In practice, this was NOT happening.
* Add a method
* change some uses of NH.getNode() in a bool context to use !NH.isNull()
* Fix a bunch of places where we depended on the (undefined) order of
  evaluation of arguments to function calls to ensure that getNode() was
  called before getOffset().  In practice, this was NOT happening.


git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@17354 91177308-0d34-0410-b5e6-96231b3b80d8

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