WebCrypto: Add algorithm normalization rules for RSASSA-PKCS1-v1_5.

BUG=245025

Review URL: https://chromiumcodereview.appspot.com/21759002

git-svn-id: svn://svn.chromium.org/blink/trunk@155458 bbb929c8-8fbe-4397-9dbb-9b2b20218538