Merge pull request #2671 from lambdageek/dev/monoerror-mono_runtime_class_init

[runtime] Use MonoError for mono_class_vtable_full and mono_runtime_class_init_full

Switch from a boolean `raise_on_error` arg to a MonoError outarg and let
callers decide what to do with the error.

Also mark mono_runtime_class_init external only.  Runtime should use
mono_runtime_class_init_full.

diff --cc mono/metadata/class-internals.h
Simple merge

diff --cc mono/metadata/icall.c
Simple merge

diff --cc mono/metadata/object-internals.h
Simple merge

diff --cc mono/metadata/object.c
Simple merge

diff --cc mono/mini/aot-runtime.c
Simple merge

diff --cc mono/mini/jit-icalls.c
Simple merge

diff --cc mono/mini/method-to-ir.c
Simple merge

diff --cc mono/mini/mini-runtime.c
Simple merge

diff --cc mono/mini/mini.c
Simple merge