bug here: https://groups.google.com/a/chromium.org/forum/?fromgroups#!topic/chromium-bugs/eUfzp3UJDwo%5B1-25%5D
just encountered this problem, streaking up my screen
The issue causing these visual anomalies has been confirmed fixed in the latest canary build of chrome (>= 25.0.1365.1 canary), so hopefully the chrome stable channel should have the fix fairly soon.