The ArrayBuffer and SharedArrayBuffer constructors should raise an
exception when called with no arguments or undefined length.  Also
unified the ArrayBuffer and SharedArrayBuffer implementations as C++
builtins, and removed some (now) obsolete runtime entries.

R=yangguo@chromium.org

Review URL: https://codereview.chromium.org/1500543002

Cr-Commit-Position: refs/heads/master@{#32590}