Revert "t/test_lib: avoid naked bash arrays in file_lineno"

This reverts commit 303775a;
instead of trying to salvage the tap-breaking change, let's
revert the whole thing for now.

Author: gitster

t/test-lib.sh

@@ -677,16 +677,14 @@ die () {
 
 file_lineno () {
 	test -z "$GIT_TEST_FRAMEWORK_SELFTEST" && test -n "$BASH" || return 0
-	eval '
-		local i
-		for i in ${!BASH_SOURCE[*]}
-		do
-			case $i,"${BASH_SOURCE[$i]##*/}" in
-			0,t[0-9]*.sh) echo "t/${BASH_SOURCE[$i]}:$LINENO: ${1+$1: }"; return;;
-			*,t[0-9]*.sh) echo "t/${BASH_SOURCE[$i]}:${BASH_LINENO[$(($i-1))]}: ${1+$1: }"; return;;
-			esac
-		done
-	'
+	local i
+	for i in ${!BASH_SOURCE[*]}
+	do
+		case $i,"${BASH_SOURCE[$i]##*/}" in
+		0,t[0-9]*.sh) echo "t/${BASH_SOURCE[$i]}:$LINENO: ${1+$1: }"; return;;
+		*,t[0-9]*.sh) echo "t/${BASH_SOURCE[$i]}:${BASH_LINENO[$(($i-1))]}: ${1+$1: }"; return;;
+		esac
+	done
 }
 
 GIT_EXIT_OK=