[1/2] Base: DownloadManager: add support pause/resume/stop notifications

Add pause, resume and stop functions to make user can pause, resume and stop downloads by manual in downloads application.

Change-Id: I82ffff5a539448faab8933e2b47591199bf24cb9
Revert "clear all recents button"

This reverts commit 72e841e576a127893cb7be77082193b6cf76bd01.

Conflicts:

	packages/SystemUI/src/com/android/systemui/recent/RecentsPanelView.java
Recents: Clear all button for recent apps.

An icon will appear on navbar when there are apps available to be killed on recent apps.

Credits to @BigBrother1984 for kitkat porting from jellybean

Patchset 2: Tablet mode is deprecated now, so no need of multiple callbacks
Patchset 3: Remove copyright from unaffected files
Patchset 4: Remove unused imports

Change-Id: I93d1d4cb34325190b03ae3a0d40e1bc170c92d91
Update clear all drawables

Signed-off-by: Andre Saddler <dresadd09691@gmail.com>
Change-Id: I8ee251b5e2144b2fd62f26cb29a0721d6b3bb72b
Recents: Always show translucent decor
SystemUI: prevent NPE on clear recents double press

Pressing Clear all button twice fast or while the list
is clearing but not yet fully cleared causes sysui to crash due to
mRecentTaskDescriptions being null: (http://pastebin.com/2gRFvf8k)

Change-Id: I23d10edfd336041739fe80352ee01987e671dbd7
Recents: ClearAll: Fix glitch on quick double tap

To reproduce:
Open five or more apps, open recents and tap twice very quick on
clear all button.

Setup a boolean to control the thread starting, don't relaunch if
clearAll's run() has been executed and is already firing up childs.

Along with this https://gerrit.paranoidandroid.co/#/c/4346/ UI/UX should
look great no matter how crazy and how many times the user click on recents.

Signed-off-by: Carlo Savignano <stevewatersy@gmail.com>
Change-Id: I0d393838c23e2585222cf7b181c2f7a6385494cd