What's this? Apparently, Google sneakily rocked out a new and previously unknown Android 5.0.2 update for the original Nexus 7 2012 WiFi tablet. This is obviously meant to address some of the bugs which Android 5.0 brought to the party for the venerable tablet.
This version is LRX22G and specifically addresses "issues with MountService which should now start before performBootDexOpt [and] changes related to NAND have also been pushed. Fstrim, introduced in Android 4.3, caused some serious issues on Lollipop… devices with slow NAND should now have a noticeable performance boost.” ~ XDA Developers
Here's a link to grab it for a manual update: Google