RegExp: Remove bogus assumptions about case independence and Latin1
RegExp: Remove bogus assumptions about case independence and Latin1

Tests are already there in mjsuint/regress/regress-latin-1.js
R=yangguo@chromium.org
BUG=v8:3550
LOG=n

Review URL: https://codereview.chromium.org/1188793004

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#29068}

UniversalFuture/moosh,UniversalFuture/moosh,UniversalFuture/moosh,UniversalFuture/moosh