2009-06-24  Emmanuel Briot  <briot@adacore.com>

	* gnatcmd.adb, make.adb, mlib-prj.adb, prj.adb, prj.ads, clean.adb,
	prj-nmsc.adb, prj-env.adb, prj-proc.adb (Units_Table): Removed, since
	no longer useful.
	(Source_Data.Lang_Kind): Removed, since it duplicates information
	already available through Language.Config.
	(Source_Data.Compile): Removed, since information is already available
	through the language.
	(Is_Compilable): New subprogram.
	(Source_Data.Dependency): Removed, since already available through
	the language.
	(Source_Data.Object_Exist, Object_Linked): Removed since available
	through the language already.
	(Unit_Data.File_Names): Is now also set in multi_language mode, to
	bring the two modes closer in the resulting data structures.
	(Source_Data.Unit): Now a direct pointer to the unit data, rather than
	just the name that would point into a hash table.
	(Get_Language_From_Name): New subprogram.

From-SVN: r148901