Refactor webcrypto unittests.

Extracts some helper functions which will be re-used for AES-CBC tests. Notably, importing of secret keys and comparison of arraybuffer against hex string.

BUG=245025

Review URL: https://codereview.chromium.org/24237013

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@225365 0039d316-1c4b-4281-b951-d872f2087c98
2 files changed