RFR (M) 8058259: compute_offset() is confusing for static fields

[coleen.phillimore at oracle.com]

Summary: remove most hard-coded offsets, have compute_offset function 
that takes a string and creates a TempNewSymbol, have 
static_field_addr() not add in 
InstanceMirrorKlass::offset_of_static_fields, ie use offset from find_field

The jvmci code uses find_field to get the offset of static fields, then 
used static_field_addr() and then subtracted 
InstanceMirrorKlass::offset_of_static fields because the function 
expected the hardcoded offsets.  Removed hardcoded static offsets and 
non-static offsets where possible.

This change also removes the nonproduct flag 
CheckAssertionStatusDirectives (default false).

Tested with tier1-5 tests on Oracle platforms, and temporary code to get 
failures in known class layouts, and see error logging.

open webrev at http://cr.openjdk.java.net/~coleenp/8058259.01/webrev
bug link https://bugs.openjdk.java.net/browse/JDK-8058259

thanks,
Coleen