Dont-clobber data-parsoid during tpl-encap

* During template encapsulation, when template ranges are
  updated, data-parsoid from the meta-element was being cloned
  over to the start element. This led to lost annotations like
  stx=html where present.

  Ex: In {{echo|<div>foo</div>}} the <div> lost the stx=html
  annotation.

* This patch just copies over dsr and src parameters.

* No change in parser tests.

Change-Id: I725bb78c5900f193c2585de38956d9138339f138
Merge "Dont-clobber data-parsoid during tpl-encap"