Regenerating generated-configure.sh produces a version from which the configure script argument runstatedir is removed.

The jdk8u-dev commit that added runstatedir is:
http://hg.openjdk.java.net/jdk8u/jdk8u-dev/rev/0a7e81cbb5f7

The jdk8u commit that added it is:
http://hg.openjdk.java.net/jdk8u/jdk8u/rev/0a7e81cbb5f7

These are both merge commits, so the source is unclear.

The output of hg diff is:

diff -r 156403f25b04 common/autoconf/generated-configure.sh
--- a/common/autoconf/generated-configure.sh Tue May 04 05:57:10 2021 +0100
+++ b/common/autoconf/generated-configure.sh Fri May 07 16:22:22 2021 +0000
@@ -1013,7 +1013,6 @@
 docdir
 oldincludedir
 includedir
-runstatedir
 localstatedir
 sharedstatedir
 sysconfdir
@@ -1256,7 +1255,6 @@
 sysconfdir='${prefix}/etc'
 sharedstatedir='${prefix}/com'
 localstatedir='${prefix}/var'
-runstatedir='${localstatedir}/run'
 includedir='${prefix}/include'
 oldincludedir='/usr/include'
 docdir='${datarootdir}/doc/${PACKAGE_TARNAME}'
@@ -1509,15 +1507,6 @@
   | -silent | --silent | --silen | --sile | --sil)
     silent=yes ;;
 
- -runstatedir | --runstatedir | --runstatedi | --runstated \
- | --runstate | --runstat | --runsta | --runst | --runs \
- | --run | --ru | --r)
- ac_prev=runstatedir ;;
- -runstatedir=* | --runstatedir=* | --runstatedi=* | --runstated=* \
- | --runstate=* | --runstat=* | --runsta=* | --runst=* | --runs=* \
- | --run=* | --ru=* | --r=*)
- runstatedir=$ac_optarg ;;
-
   -sbindir | --sbindir | --sbindi | --sbind | --sbin | --sbi | --sb)
     ac_prev=sbindir ;;
   -sbindir=* | --sbindir=* | --sbindi=* | --sbind=* | --sbin=* \
@@ -1655,7 +1644,7 @@
 for ac_var in exec_prefix prefix bindir sbindir libexecdir datarootdir \
                datadir sysconfdir sharedstatedir localstatedir includedir \
                oldincludedir docdir infodir htmldir dvidir pdfdir psdir \
- libdir localedir mandir runstatedir
+ libdir localedir mandir
 do
   eval ac_val=\$$ac_var
   # Remove trailing slashes.
@@ -1808,7 +1797,6 @@
   --sysconfdir=DIR read-only single-machine data [PREFIX/etc]
   --sharedstatedir=DIR modifiable architecture-independent data [PREFIX/com]
   --localstatedir=DIR modifiable single-machine data [PREFIX/var]
- --runstatedir=DIR modifiable per-process data [LOCALSTATEDIR/run]
   --libdir=DIR object code libraries [EPREFIX/lib]
   --includedir=DIR C header files [PREFIX/include]
   --oldincludedir=DIR C header files for non-gcc [/usr/include]
@@ -4394,7 +4382,7 @@
 #CUSTOM_AUTOCONF_INCLUDE
 
 # Do not change or remove the following line, it is needed for consistency checks:
-DATE_WHEN_GENERATED=1613496357
+DATE_WHEN_GENERATED=1620404533
 ###############################################################################
#