Fix issue with abi split when there's no universal pkg.

The issue came from the process resource task that
generates the R class. Only one of the outputs' task
is setup to generate the R class, but it only
happened if an output had no filter for abi or density.

Now we just find the first one to not have a density filter
and use it.

Also, converted ndkSanAngeles sample to use the new split
mechanism.

Change-Id: I44becc559b90b53f77561c68020725e60daa749a
Change java compile task to generic compile task in model

The previous model included a task to allow compiling
only up to the Java code for a given artifact. This did
not include native code, so the new model has a generic
compile task instead.

The old java compile task is still there for now but will be
removed in 1.0

Change-Id: I030a069130613fee5692123966d1acc1d0926996
Merge "Fix issue with abi split when there's no universal pkg." into idea133
Merge "Change java compile task to generic compile task in model" into idea133
Use daemon threads for battery and property background fetches.

The thread pool previously used had no benefit over a simple thread,
since there was a thread pool per device.

Using daemon threads so having an active prop or battery query does not
prevent JVM from shutting down.

Also remove the battery fetch backoff time to be consistent with
property fetch.

Change-Id: Ica14c161462f7a5ee1729d87228f4d13fb28de63
Merge "Use daemon threads for battery and property background fetches." into idea133
Fix test due to compile task change in the model.

Change-Id: Id9effc1f682ddd6d6b302bb077f354d81ab2b973
Merge "Fix test due to compile task change in the model." into idea133
Add ability to mock LayoutLibrary

Add a default constructor that may be used to instantiate LayoutLibrary
for the purpose of testing.

Change-Id: I42e40da0927249fa2c5d10fd3f5f993c42388101
Merge "Add ability to mock LayoutLibrary" into idea133