Use table's tsr info for encapsulating transclusion meta.

The earlier implementation searched the table's siblings for tsr[0] to
avoid the case where the table's tsr[1] wasn't present.

However, since d05894f170ba8e9a712099d3e6e6cd48ff53808d, encapsulation
doesn't happen when the foster box, and thus the table, are in the
transclusion. So, tsr[1] should always be available.

Fixes regression introduced in 1dba828d7eddf9f00aea6b47242ecfc4aedcdd07.

Change-Id: I2da552b102c666f4942f07b1ac56163552d2a401
Merge "Use table's tsr info for encapsulating transclusion meta."