Embedders that passed in non-primitive values should either use
getters/setters (templates) or install a native data property,
otherwise, the values would all result in cross-context leaks

BUG=none
R=verwaest@chromium.org
LOG=y

Review URL: https://codereview.chromium.org/1839983002

Cr-Commit-Position: refs/heads/master@{#35244}