Move default libnativehelper include to mock dir.

include_deprecated contains all of the
headers that are currently used by libraries without
the "nativehelper/" prefix.

The current count of this is this:
      2 ScopedLocalFrame.h
      4 JniInvocation.h
      4 ScopedBytes.h
      5 AsynchronousCloseMonitor.h
      6 toStringArray.h
      7 ScopedStringChars.h
     38 JniConstants.h
     41 ScopedPrimitiveArray.h
     79 ScopedUtfChars.h
     80 UniquePtr.h
    100 ScopedLocalRef.h
    467 JNIHelp.h

Now we can remove each file from the global header include
on a file by file basis.

Bug: 63762847
Test: libraries still find their headers

Change-Id: I77f1dcff47389bcce55087fe18c46350992e4e06