Add session_class, which defines a JSObject wrapper for struct session.
Add location_array_class, which defines a JSObject wrapper for struct
ses_history. The "history" member of struct session is a struct
ses_history, which is a linked list of struct location.
Add a pointer from struct session to the session_class object and the
location_array object.
Add smjs_get_session_object to return a session_class JSObject wrapper for
a given struct session.
Add smjs_get_session_location_array_object to return a location_array_class
JSObject wrapper for a given struct session.
Add "session" property to the "elinks" object, which uses
smjs_get_session_object to get a JSObject wrapper for smjs_ses.
Add smjs_location_array_get_property, which allows indexing
a location_array object using a positive number for history forward or
a negative number for history backward.
Add session_props, session_get_property, session_set_property,
session_funcs, smjs_session_goto_url (which implements the "goto" method),
and smjs_init_session_interface for session_class.
Add session_construct, which creates a new tab and returns the JSObject
session_class wrapper.
Add session_finalize and smjs_location_array_finalize, which clear the
pointers between struct session and the JSObject wrappers in question.
Add smjs_detach_session_object, which clears the pointers between a given
struct session and the corresponding JSObject wrappers.
In destroy_session, call smjs_detach_session_object.
Add jsval_to_object helper in ecmascript/spidermonkey/util.h;
jsval_to_object is used in smjs_session_goto_url.
Modify delayed_goto_uri_frame to allow the target to be NULL.
smjs_session_goto_url needs this modification.
Rename src/ecmascript/spidermonkey/util.c to
src/ecmascript/spidermonkey-shared.c and compile it also when
CONFIG_SCRIPTING_SMJS is enabled but CONFIG_ECMASCRIPT_SPIDERMONKEY is
not. Then use its functions from src/scripting/smjs/ too. Move the
corresponding declarations, as well as the inline functions needed by
src/scripting/smjs/, from src/ecmascript/spidermonkey/util.h to
src/ecmascript/spidermonkey-shared.h.
ELinks is nowadays using two JSRuntimes and SpiderMonkey has bugs that
make it crash in such use. To work around them, ELinks will need to
be changed to use only one JSRuntime. I am planning to define and
initialize that JSRuntime in src/ecmascript/spidermonkey-shared.c,
now that it's compiled whenever either of the modules is enabled.
