Pepper: Refactor OpenManifestEntry.

This change pulls out more OpenManifestEntry code from service_runtime, making
PPB_NaCl_Private a smallter interface, and preparing for pulling all of that
logic out of the trusted plugin.

An earlier version of this change was reverted after breaking Non-SFI mode, but
the Non-SFI case no longer uses this codepath.

CQ_EXTRA_TRYBOTS=tryserver.chromium:linux_rel_precise32
BUG=239656

Review URL: https://codereview.chromium.org/357773002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@279832 0039d316-1c4b-4281-b951-d872f2087c98
5 files changed