Pepper: Simplify Pnacl manifest id logic.

This removes some unnecessary manifest_id storage and passing to make manifest
behavior clearer in the trusted plugin. Helper NaCl Modules (llc and ld) always
use the "Pnacl Manifest" for resolving keys, as there is no relevant
json-formatted NMF available.

BUG=239656
R=dmichael@chromium.org

Review URL: https://codereview.chromium.org/292743011

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@272582 0039d316-1c4b-4281-b951-d872f2087c98
6 files changed