JNI warnings cleanup, on Windows

Running FX demos (Ensemble, Ensemble3) with -Xcheck:jni reveals the following issue:

1. Java_com_sun_prism_d3d_D3DResourceFactory_nUpdateTextureF

env->GetArrayLength() is called within Get/ReleasePrimitiveArrayCritical() block

2. Another similar issue is somewhere in web component code, information is to come.