Revert 167430 "Disabled newly added visible content rect tests."

> Disabled newly added visible content rect tests.
> 
> Tests were broken on Android. Disabling to allow a Blink roll while I
> fix the tests.
> 
> TBR=bokan@chromium.org
> 
> Review URL: https://codereview.chromium.org/162613009

TBR=acolwell@chromium.org

Review URL: https://codereview.chromium.org/172863005

git-svn-id: svn://svn.chromium.org/blink/trunk@167445 bbb929c8-8fbe-4397-9dbb-9b2b20218538