Item frames pop off of wall and chests are empty when updated to 1.7.7

Put the summary of the bug you're having here

What I expected to happen was...:
I updated to 1.7.7

What actually happened was...:
all of my items within chests were gone, item frames had popped off of the walls, and my inventory was empty including armor.

Steps to Reproduce:
1. update to 1.7.7
2. load a world created previous
3. ...