src: remove container_of, use CONTAINER_OF

CONTAINER_OF was introduced a while ago but was not used consistently
everywhere yet.  This commit fixes that.

Why CONTAINER_OF instead of container_of?  The former makes it crystal
clear that it's a macro, not a function.
build: make v8 use random seed for hash tables

Upstream V8 as of commit v8/v8@4bc70e8 uses a fixed seed of 314159265
for hash tables unless instructed otherwise.  Tell V8 to keep using a
random seed.