Unification of jni_<platform>.h

[dean.long at oracle.com]

On 10/18/17 6:10 AM, Magus Ilse Bursie wrote:

> For jni_arm.h: Finally, the jni_arm.h (the 32-bit formerly closed 
> Oracle port), the JNIEXPORT/JNIIMPORT is different, by defining 
> __attribute__((externally_visible)). This might have been relevant due 
> to compile/link time symbol processing for that platform, but 
> technically it should probably not have been connected to the platform 
> per se, but rather to the compilation procedure. Since the arm-32 
> platform is kind of abandoned right now, I propose to modify the 
> compilation to be more standard, if this is required, rather than 
> keeping these attributes. 
I think that was needed for gcc link-time optimization support, so it's 
really gcc-specific and not arm-specific.

dl