DocumentsUI: Add a standalone File Manager

This commit adds a standalone mode to the DocumentsUI, to let
it act as a file manager/explorer.
You can browse your storage contents, open files, and delete them,
as well as do everything that the DocumentsUI can do (ie. sort
by name/size/type, list and grid view, recents, search, ...).

This gives us a consistent file browsing UX accross all apps
that uses the new documents API.

Change-Id: If73a3c100f010bdb766c843976d4fd3573ea805c
Merge branch 'kitkat' of https://github.com/AOSPA/android_frameworks_base into kitkat
Properly handle null URIs.

Change-Id: Ib81044686f40284bacf6ee645c671679f62be843
JIRA:CYAN-2491
Remove 'force overflow button' logic.

It's force-enabled now anyway.

Change-Id: Ib4489456d40650316d45865fedfae9c3c960b81e

Conflicts:

	core/java/android/provider/Settings.java
base: added national roaming info for Play in Poland

Cherry-picked from OmniROM:
https://gerrit.omnirom.org/#/c/3382/

Users of Play in Poland (MCC 260 MNC 06) can roam on
Plus, T-Mobile, Orange (MNCs 01/02/03)

Change-Id: I8ea62b0ca40bac9ced11802ee8ef583d6392a199
Telephony: Add data rat constant

This event constant is used in DcTracker

Change-Id: I1f9b34a8689c43c2586e9e3a92f0453649775d73
(cherry picked from commit f7ca98035479b670ff51bc9298fd7928a5e0f80d)
(cherry picked from commit f4d8f7b8fa390302b9cc51a5640e017ff393dfcc)
(cherry picked from commit 77d810390fbca8cb1d10bce148035fada414e0eb)
National roaming info for Drei in Austria

3AT roams in T-Mobile AT networks

Change-Id: I915edccf92bcbb088fa25b958eb345c624f61597
Bluetooth: HID: Add support for HID Device Role

This patch adds the HID Device Role support in Bluetooth framework.
Also AIDL and callback related files for HID Device role are added
to provide interface for third party applications to communicate with
HID device Service.

Change-Id: Id03a362b7bcfa2e76056fa0197eaac12ce49b5a2
CRs-Fixed: 573086
OBEX: Reduce Obex MTU size for A2DP or SCO concurrency

Reduce Obex MTU to 8k from 64k when OPP send is tried with
SCO / A2DP streaming in progress, so that the continue
response for first complete Obex PUT packet is received
from SOC within 50 seconds time frame.

CRs-Fixed: 571865
Change-Id: I1eae114f57f2a92ee4b26c82d8f55fafe02775b8
Bluetooth: Changes for LPP and extended LE scan

This patch includes implementation of a new Bluetooth
Adapter named QBluetoothAdapter for implementing LE
specific tasks that the default adapter doesnt perform.
This patch also implements Low power proximity and extended
LE scan functionality based on service UUIDs.

CRs-Fixed: 581289
Change-Id: I63e0593f79c8929d4e18cee0472fcb401c8892e7
Merge remote-tracking branch 'legacy/kitkat' into kitkat