NFC: getNdefMessage() should throw exception if no tag in field.

According to documentation, an TagLostException should be thrown, if
the tag has been moved out of field when reading NDEF message.

Change-Id: Ib7e485ed442027fdebd5bc7a46101fbca0c88bdb
NsdService does not clean up after exiting clients

When a client of the NsdService exits, NsdService should
clean up the requests it has sent to the mDNS daemon:
cancel any pending resource-discovery and resource-resolution
queries, and remove any services registered by this client.

If this isn't done, several bad things happen. The daemon will
continue to run unnecessarily, will report service discoveries
that can't be forwarded on to the client, and will continue to
advertise service ports for an application which is no longer
running until the device is rebooted (mDNS pollution).

Bug: 9801184
Change-Id: I0aa7311480322aefcff16f902fbbf34f50985d38
Null pointer exception in FileRotator.java

Sometimes a null pointer exception is thrown when examining files
managed by the file rotator.

The logs from the test show that the Wifi state is changed a large
number of times. On every state change, a write operation is
initiated on the file system. This will eventually result in out
of memory and the call to mBasePath.list() in the maybeRotate(...)
method in FileRotator.java will return null so the iteration will
throw a NullPointerException.

Change-Id: I5d5980d9593bc9ec75281169ca27ee591809903f
Prevent a duplicated registration of Observers

If same Observer and same URI are registered, the callback functions are called multiple times
when data identified by a given content URI changes.
It makes system slow and it cause ANR sometimes.
And When run unregisterContentObserver(), just one deleted
but others are remained in mObservers.
So add prevent code to avoid to duplicated registraion of Observers

Change-Id: I5c7845deb682db289ff0d53150ef012174859767
Signed-off-by: muzbit.kim <muzbit.kim@lge.com>
Framework: Add Landscape layout for ECA

Maintainers!!!
Please test on your devices.
MAYBE google did this for a reason =P

PS2: Whitespace

Change-Id: I22829c6e5f8badf78336e5c14d3c507426da32b9
Lockscreen Blur: Disable if music is playing

Some apps don't employ full screen album art.
In that case album art doesn't override wallpaper & content behind screen is clearly visible.
This fixes that issue.