Steam: "You are missing the following 32-bit libraries, and Steam may not run: libdrm.so.2"

It is the weirdest. I opened up my Steam and suddenly received this message when it had been working perfectly fine a couple of days before:

It was already installed. I tried reinstalling Steam from the package in the Steam website. I also tried purging libdrm2 and reinstalling. I tried just restarting the system. I tried updating and upgrading all components. No change.

No Google results have turned up anything that makes sense in my situation.

I'm running on Ubuntu 14.04 .

It turns out that Steam is 32-bit and the 64-bit libdrm2 package I have is obviously not being recognized. This was clear from the console output when running the "steam" executable directly:

$ steam
Failed to parse arguments: Option "--disable-factory" is no longer supported in this version of gnome-terminal.
Package libgl1-mesa-dri:i386 needs to be installed
Package libgl1-mesa-glx:i386 needs to be installed
Running Steam on ubuntu 14.04 64-bit
STEAM_RUNTIME is enabled automatically
Pins up-to-date!
Error: You are missing the following 32-bit libraries, and Steam may not run:
libdrm.so.2
Installing breakpad exception handler for appid(steam)/version(1513371133)
Installing breakpad exception handler for appid(steam)/version(1513371133)
Installing breakpad exception handler for appid(steam)/version(1513371133)
Failed to load steamui.so - dlerror(): libdrm.so.2: wrong ELF class: ELFCLASS64
Installing breakpad exception handler for appid(steam)/version(1513371133)

The first comment indicates that it needs to be 32-bit. The second indicates that the 64-bit one isn't what it wanted.

Simply fixed by installing "libdrm2:i386":

$ sudo apt-get install libdrm2:i386