Bug#647053: Reverse dependencies of virtual package not handled correctly

[Dmitry Katsubo <dma_k@mail.ru>]

I've hit the same problem when listing dependencies for package tomcat8, which depends on tomcat8-common, which depends on "default-jre-headless | java8-runtime-headless | java8-runtime,
libtomcat8-java" but java8-runtime-headless is not shown:

# apt-rdepends --state-follow=Installed --state-show=Installed tomcat8

tomcat8
  Depends: tomcat8-common (>= 8.5.38-2)
...
tomcat8-common
  Depends: libtomcat8-java (>= 8.5.38-2)


# apt-cache showpkg java8-runtime-headless
...
Reverse Provides:
openjdk-8-jre-headless 8u212-b01-1~deb9u1 (= )
openjdk-11-jre-headless 11.0.3+1-1~bpo9+1 (= )
openjdk-8-jre-headless 8u181-b13-2~deb9u1 (= )
default-jre-headless 2:1.8-58 (= )
openjdk-11-jre-headless 11.0.3+1-1 (= )
default-jre-headless 2:1.11-71 (= )

-- 
With best regards,
Dmitry