avoid adblockplus.org to change its URL to platform-specific path

[philll]

Background

Journalists and other people linking to adblockplus.org very often don't recognize the platform-specific redirect and thus link to the URL matching their browser platform instead of the generic URL. Users opening this link with another browser are then confused about the grey download link. To avoid this to happen without breaking the possibility of specifically linking to a platform-specific version of the website, we want to have internal redirects instead of redirecting the user himself.

What to change

Avoid adblockplus.org to change its URL to a platform-specific path in the user's browser, while keeping the possibility of specifically linking to a platform-specific version of the website.

[trev]

I decided to push this change already because the approach has been discussed and Felix is currently on vacation. This still needs to be reviewed however.

[trev]

I had to implement redirects for language-independent URLs like ​https://adblockplus.org/chrome - selecting a different browser wouldn't work correctly otherwise.

There is also an effect that might not be desirable: ​https://adblockplus.org/bg won't redirect either. This means however that browser switching links point to ​https://adblockplus.org/chrome for example and ignore the selected language (Bulgarian in this case). So maybe we want to keep the redirect for ​https://adblockplus.org/bg. Alternatively, we can always redirect ​https://adblockplus.org/bg to ​https://adblockplus.org/bg/.

[trev]

Alternatively, we can always redirect ​​https://adblockplus.org/bg to ​​https://adblockplus.org/bg/.

Implemented this, not having ambiguous URLs here seems to be a good idea anyway.

[trev]

Got LGTM in the review. The changes themselves have been applied a while ago.

[till]

This fix doesn't solve the problem for existing links (e.g. here: ​http://www.huffingtonpost.com/2014/08/15/pop-up-ads-sorry-ethan-zuckerman_n_5681439.html).

[trev]

Yes, as discussed. We cannot do this without breaking the platform switching mechanism.