Update vendor directory

Re-added cobra patch 499475bb41

vendor/google.golang.org/appengine/internal/regen.sh

@@ -23,14 +23,18 @@ echo 1>&2 $pkgdir
 base=$(echo $pkgdir | sed "s,/$PKG\$,,")
 echo 1>&2 "base: $base"
 cd $base
-for f in $(find $PKG/internal -name '*.proto'); do
-	echo 1>&2 "* $f"
-	protoc --go_out=. $f
+
+# Run protoc once per package.
+for dir in $(find $PKG/internal -name '*.proto' | xargs dirname | sort | uniq); do
+	echo 1>&2 "* $dir"
+	protoc --go_out=. $dir/*.proto
 done
 
-# Fix up import lines.
-# This should be fixed upstream.
-# https://code.google.com/p/goprotobuf/issues/detail?id=32
 for f in $(find $PKG/internal -name '*.pb.go'); do
-  sed -i '/^import.*\.pb"$/s,/[^/]*\.pb"$,",' $f
+  # Remove proto.RegisterEnum calls.
+  # These cause duplicate registration panics when these packages
+  # are used on classic App Engine. proto.RegisterEnum only affects
+  # parsing the text format; we don't care about that.
+  # https://code.google.com/p/googleappengine/issues/detail?id=11670#c17
+  sed -i '/proto.RegisterEnum/d' $f
 done