doublestatic: fix dependencies if two files depend on one non-generated file.

If a and b both depend on c, and c is a static (non-generated) file that has
changed since the last successful build of a and b, we would try to redo
a, but would forget to redo b.  Now it does both.

t/deps/.gitignore

@@ -3,4 +3,5 @@ t2.count
 overwrite
 overwrite[123]
 genfile2
-genfile.log
+genfile.log
+static.log

t/deps/clean.do

@@ -1,4 +1,3 @@
 redo basic/clean dirtest/clean
-rm -f *~ .*~ *.count t1a overwrite overwrite[123] genfile2 genfile.log
-
-
+rm -f *~ .*~ *.count t1a overwrite overwrite[123] \
+	genfile2 genfile.log static.log

t/deps/doublestatic.do

@@ -0,0 +1,10 @@
+rm -f static.log
+
+redo static1 static2
+
+touch static.in
+. ../flush-cache.sh
+redo-ifchange static1 static2
+
+COUNT=$(wc -l <static.log)
+[ "$COUNT" = 4 ] || exit 55

t/deps/static1.do

@@ -0,0 +1,2 @@
+redo-ifchange static.in
+echo $$ >>static.log

t/deps/static2.do

@@ -0,0 +1,2 @@
+redo-ifchange static.in
+echo $$ >>static.log

t/deps/test.do

@@ -1 +1,2 @@
-redo test1 test2 ifchange-fail overwrite gentest basic/test dirtest/test
+redo test1 test2 ifchange-fail overwrite gentest doublestatic \
+	basic/test dirtest/test