There are a lot of tests in cctest/test-parsing/ErrorsArrowFunctions,
so it is quite slow. This patch removes some flags to make it faster.
Removing three flags that don't affect the test brings down the run
time one order of magnitude, which is fast enough even for debug/ASAN
bots.

Also, remove the unneeded kArrowFunctions flag from
cctest/test-parsing/NoErrorsYieldSloppyAllModes

BUG=
R=marja@chromium.org

Review URL: https://codereview.chromium.org/387383002

Patch from Adrián Pérez de Castro <aperez@igalia.com>.

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@22392 ce2b1a6d-e550-0410-aec6-3dcde31c8c00