As announced back in December, Google stopped supporting Google Chrome on 32-bit Linux starting this month. Users running a 32bit Linux distribution are advised to stop using Google Chrome because, while it will continue to work, it will no longer receive any updates (including no security fixes).
The 32-bit build configurations for Chromium continues to be supported, so you can still use Chromium browser on 32-bit Linux distributions.
Because the official Google Chrome repository no longer provides 32-bit packages, 64-bit Ubuntu/Debian users will notice an error when updating the software sources, which looks as follows:
Failed to fetch http://dl.google.com/linux/chrome/deb/dists/stable/Release Unable to find expected entry 'main/binary-i386/Packages' in Release file (Wrong sources.list entry or malformed file) Some index files failed to download. They have been ignored, or old ones used instead.
To fix this error on Ubuntu/Debian 64-bit, the repository must be specifically set for 64-bit only - this can be done by adding "[arch=amd64]" after "deb" in the /etc/apt/sources.list.d/google-chrome.list. To do this automatically, you can use the following command:
sudo sed -i -e 's/deb http/deb [arch=amd64] http/' "/etc/apt/sources.list.d/google-chrome.list"
Update: this file is changed on each Google Chrome update and it looks like there's no way around that (changing /opt/google/chrome/cron/google-chrome or /etc/default/google-chrome doesn't affect this) so until Google changes this in its package, you'll need to apply the fix above after every Google Chrome update. If you have a solution for this, let us know in the comments!
Update 2: A workaround would be to make the .list file immutable, so it can't be changed by any Google Chrome updates, by using "sudo chattr +i /etc/apt/sources.list.d/google-chrome.list" (which can be reversed using: "sudo chattr -i /etc/apt/sources.list.d/google-chrome.list") but this is not ideal and you should change this file back once Google fixes this on their end.
Update 3: this bug was fixed upstream in version 49.0.2623.87 (thanks to Segio Rus for the comment!), so updating to Google Chrome 49.0.2623.87 should fix this issue.
On 32-bit, you should remove the repository and stop using Google Chrome since it won't receive any security updates:
sudo rm /etc/apt/sources.list.d/google-chrome.list sudo apt-get remove google-chrome
thanks to darkfur93 @ reddit for the info (and to Bruce Ingalls for the tip)