Read PNaCl fingerprint from disk.

This change is redundant given the pending refactoring of the PNaCl
installer, but that change is blocked on resolving the on-demand
feature. In the meantime, we want to read the read the diff update
fingerprint from disk to avoid distributing the wrong delta blobs.

BUG=245318

Review URL: https://codereview.chromium.org/24532003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@225490 0039d316-1c4b-4281-b951-d872f2087c98
[Android] When toggling AX script inject, also set native AX state.

When we enable/disable script injection, also update the flag that
says whether we should use native accessibility.

BUG=

Review URL: https://codereview.chromium.org/24559002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@225491 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 225490
SVN changes up to revision 225491