android: improve error messages in DirectBufferAllocator

Change-Id: Iefab77e543606cfad937a79743fb3b9a68a0f2a2
android: extract gathering document info into postLoad method

Change-Id: Id90680d3b207973b55927add1c91111268bb2a48
lok: improve error reporting in lok implementation

Change-Id: Ifc7b18e173b0c91c24a53fad9c35ac3a34a4b33e
android: use different function to prevent stripping JNI symbols

Change-Id: Ib003da5c7fec7fc3783f01a33a63deb384c7e770
android: cleanup LibreOfficeKit initialization in Java

Change-Id: I7688968e92ae4b3d6fef19c4544ae91bdcd8b1b9
android: use ByteBuffer to send or store pointers in JNI bindings

Using direct ByteBuffer is much nicer option to store or send
pointers between C(++) code and Java via JNI as it handles endiness
and pointer size for us. Using "long" type can have unexpected
results in 32-bit architectures (mostly Android). This was causing
grief especially when Android introduced support for 64-bit
architectures starting with SDK 19.

Change-Id: Ie92d0f913b668e1724e846d70d1820445d9cb086