Fixed nested pdf data merging

[ExtReMLapin]

Fixes #486

Why am I the first one to meet this issue ???

[chrismattmann]

Can you add a unit test that demonstrates that this works, @ExtReMLapin ?

[chrismattmann]

@afuetterer can you take a look?

[coveralls]

coverage: 67.544% (-0.009%) from 67.553% — ExtReMLapin:fix_nested_pdf into chrismattmann:master

[afuetterer]

Sorry, no.
I don't enjoy the tone of issue and PR description and will not be a part of this interaction.

[ExtReMLapin]

IMO It's better to have E2E tests, but this one should be more than enough.
And i'm not sure about hosting this PDF or making a dummy one generated at runtime.

Anyway the test it there, it's probably better to squash commit commits on merge.

[ExtReMLapin]

@afuetterer my point there is It's surprising to see a bug caused by 11 years old code, I would have expected it to be met sooner by anyone else.

Being on the bleeding edge forces us to get bugs fixed everywhere, most of the time on "young" libraries or very actives ones.