[COMMITTERS] pgsql: Refactor bitmap heap scan in preparation for parallel support.

Refactor bitmap heap scan in preparation for parallel support.

The final patch will be less messy if the prefetching support is
a bit better isolated, so do that.

Dilip Kumar, with some changes by me.  The larger patch set of which
this is a part has been reviewed and tested by (at least) Andres
Freund, Amit Khandekar, Tushar Ahuja, Rafia Sabih, Haribabu Kommi, and
Thomas Munro.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/9e0fe09fc5dc1135479b532d1806e28cbc5a35aa

Modified Files
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src/backend/executor/nodeBitmapHeapscan.c | 148 ++++++++++++++++++------------
1 file changed, 88 insertions(+), 60 deletions(-)