lib: test-istream-concat - test only concat, not simultanious limit streams Test just concat functionality in this unit test. Simultanious access of limit streams can be tested elsewhere.
lib: test-istream-concat - test only concat, not simultanious limit streams
Test just concat functionality in this unit test. Simultanious access of
limit streams can be tested elsewhere.

Without the fix in:
  31efe2d04793 lib: istream-concat read() returned -2 too early.
The failure previously seen in test-istream-concat would be still reproducable:
test-istream-concat.c:84: Assert failed: size >= TEST_MAX_BUFFER_SIZE
istream concat random ................................................ : FAILED
test: random seed #1 was 1403118493

Signed-off-by: Phil Carmody <e888d2bd6f13f82caa51a37c03d034c76f661ba3@dovecot.fi>

dscho/dovecot,dscho/dovecot,dscho/dovecot,dscho/dovecot,dscho/dovecot