BUG #12885: The result of casting a double to an integer depends on the database version

The following bug has been logged on the website:

Bug reference: 12885
Logged by: Rich Schaaf
Email address: rschaaf(at)commoninf(dot)com
PostgreSQL version: 9.4.1
Operating system: Windows 7
Description:

The result returned by the following query appears to depend on the
PostgreSQL database version.

The query is:
select column1 AS double_value, cast(column1 AS INT) AS int_value
from (VALUES (-2.5::double precision),
(-1.5::double precision),
(-0.5::double precision),
(0.5::double precision),
(1.5::double precision),
(2.5::double precision)) t;

In PostgreSQL 9.3.5, the query returns:
double_value, int_value
-2.5, -3
-1.5, -2
-0.5, -1
0.5, 1
1.5, 2
2.5, 3

PostgreSQL 9.4.1, the query returns:
-2.5, -2
-1.5, -2
-0.5, 0
0.5, 0
1.5, 2
2.5, 2