Move class tests to es6 directory BUG=v8:3330 LOG=N R=adamk Review URL: https://codereview.chromium.org/1213813003 Cr-Commit-Position: refs/heads/master@{#29336}
TBR=dslomov@chromium.org BUG= Review URL: https://codereview.chromium.org/1027693003 Cr-Commit-Position: refs/heads/master@{#27339}