Merge branch 'bc/hash-independent-tests-part-5'

Preparation for SHA-256 upgrade continues in the test department.

* bc/hash-independent-tests-part-5:
  t4009: make hash size independent
  t4002: make hash independent
  t4000: make hash size independent
  t3903: abstract away SHA-1-specific constants
  t3800: make hash-size independent
  t3600: make hash size independent
  t3506: make hash independent
  t3430: avoid hard-coded object IDs
  t3404: abstract away SHA-1-specific constants
  t3306: abstract away SHA-1-specific constants
  t3305: make hash size independent
  t3301: abstract away SHA-1-specific constants
  t3206: abstract away hash size constants
  t3201: abstract away SHA-1-specific constants

Author: gitster

t/t3201-branch-contains.sh

@@ -192,10 +192,10 @@ test_expect_success 'branch --merged with --verbose' '
 	EOF
 	test_cmp expect actual &&
 	git branch --verbose --merged topic >actual &&
-	cat >expect <<-\EOF &&
-	  master c77a0a9 second on master
-	* topic  2c939f4 [ahead 1] foo
-	  zzz    c77a0a9 second on master
+	cat >expect <<-EOF &&
+	  master $(git rev-parse --short master) second on master
+	* topic  $(git rev-parse --short topic ) [ahead 1] foo
+	  zzz    $(git rev-parse --short zzz   ) second on master
 	EOF
 	test_i18ncmp expect actual
 '