Pick certificates using OPEN_DOC intent.

Instead of blindly scanning just primary internal storage, use the
new DocumentsUI intents to let the user select certificates from
any storage backend.  This includes both primary and secondary
external storage devices.

Bug: 11354402
Change-Id: Ia0b4bf1b30c83eb1a64b070cd2f99ad5e6498786
Import translations. DO NOT MERGE

Change-Id: Ife9390482e6ead6f379e45fafc732e49234d7277
Auto-generated-cl: translation import
Merge tag 'android-4.4.1_r1' into HEAD

Android 4.4.1 Release 1