Dpkg::ErrorHandling: Remove unused warnerror() and $warnable_error

Do not pass over -W and -E from dpkg-buildpackage to dpkg-source anymore
and warn directly about its deprecated status.

scripts/Dpkg/ErrorHandling.pm

@@ -4,11 +4,10 @@ use Dpkg;
 use Dpkg::Gettext;
 
 use base qw(Exporter);
-our @EXPORT = qw(info warning warnerror error errormsg
+our @EXPORT = qw(info warning error errormsg
                  syserr internerr subprocerr usageerr syntaxerr);
-our @EXPORT_OK = qw(report unknown $warnable_error $quiet_warnings);
+our @EXPORT_OK = qw(report unknown $quiet_warnings);
 
-our $warnable_error = 1;
 our $quiet_warnings = 0;
 
 sub report(@)
@@ -29,15 +28,6 @@ sub warning($;@)
     warn report(_g("warning"), @_) if (!$quiet_warnings);
 }
 
-sub warnerror(@)
-{
-    if ($warnable_error) {
-	warning(@_);
-    } else {
-	error(@_);
-    }
-}
-
 sub syserr($;@)
 {
     my $msg = shift;

scripts/dpkg-buildpackage.pl

@@ -9,7 +9,7 @@ use POSIX;
 
 use Dpkg;
 use Dpkg::Gettext;
-use Dpkg::ErrorHandling qw(:DEFAULT $warnable_error);
+use Dpkg::ErrorHandling;
 use Dpkg::BuildOptions;
 use Dpkg::Compression;
 use Dpkg::Version qw(check_version);
@@ -71,8 +71,6 @@ Options:
   -nc            do not clean source tree (implies -b).
   -tc            clean source tree when finished.
   -ap            add pause before starting signature process.
-  -E             turn certain warnings into errors.       } passed to
-  -W             when -E is turned on, -W turns it off.   } dpkg-source
   -i[<regex>]    ignore diffs of files matching regex.    } only passed
   -I[<pattern>]  filter out files when building tarballs. } to dpkg-source
   --admindir=<directory>
@@ -186,12 +184,9 @@ while (@ARGV) {
 	$changedby = $1;
     } elsif (/^-C(.*)$/) {
 	$desc = $1;
-    } elsif (/^-W$/) {
-	$warnable_error = 1;
-	push @passopts, '-W';
-    } elsif (/^-E$/) {
-	$warnable_error = 0;
-	push @passopts, '-E';
+    } elsif (m/^-[EW]$/) {
+	# Deprecated option
+	warning(_g("-E and -W are deprecated, they are without effect"));
     } elsif (/^-R(.*)$/) {
 	@debian_rules = split /\s+/, $1;
     } else {