A recent change to disallow wasm compilation in contexts where
CSP unsafe-eval would disallow eval also ended up banning asm.js there:
https://codereview.chromium.org/2646713002

This ends up banning non-evaled asm.js even in some places it should be
allowed.

NOTE: Although asm.js code converted to wasm generates an intermediate wasm
module. asm.js code evaled in a disallowed context can't even get
that far (as it's stoped at the eval site).

BUG=683867
R=mtrofin@chromium.org,titzer@chromium.org,adamk@chromium.org

Review-Url: https://codereview.chromium.org/2656463004
Cr-Commit-Position: refs/heads/master@{#42616}