exp_disp.adb (Export_DT): Addition of a new argument (Index)...

2009-04-09  Javier Miranda  <miranda@adacore.com>

	* exp_disp.adb (Export_DT): Addition of a new argument (Index); used to
	retrieve from the Dispatch_Table_Wrappers list the external name.
	Addition of documentation.
	(Make_Secondary_DT): Addition of a new argument (Suffix_Index) that is
	used to export secondary dispatch tables (in the previous version of
	the frontend only primary dispatch tables were exported). Addition of
	documentation.
	(Import_DT): New subprogram (internal of Make_Tags). Used to import a
	dispatch table of a given tagged type. 
	(Make_Tags): Modified to import secondary dispatch tables.

	* sem_ch3.adb (Analyze_Object_Declaration): Code cleanup.
	(Constant_Redeclaration): Code cleanup.

	* einfo.ads (Dispatch_Table_Wrapper): Renamed to
	Dispatch_Table_Wrappers.  Update documentation.

	* einfo.adb (Dispatch_Table_Wrapper, Set_Dispatch_Table_Wrapper):
	Renamed to Dispatch_Table_Wrappers.

	* sem_util.adb (Collect_Interface_Components): Improve handling of
	private types.

	* atree.ads (Elist26, Set_Elist26): New subprograms

	* atree.adb (Elist26, Set_Elist26): New subprograms

From-SVN: r145811