exmdb: ignore softdeleted folders when validating new folder name

Two folders must not have the same path. This limitation was
overeagerly enforced even for softdeleted folders, even though they
are not visible, which led to the inability in Gromox to delete and
recreate folders in public stores while the same is doable in
EXC2019.

References: GXL-454, DESK-1210

exch/exmdb_provider/common_util.cpp

@@ -1112,7 +1112,7 @@ BOOL common_util_get_folder_by_name(
 	char sql_string[128];
 
 	snprintf(sql_string, std::size(sql_string), "SELECT folder_id "
-	          "FROM folders WHERE parent_id=%llu", LLU{parent_id});
+	         "FROM folders WHERE parent_id=%llu AND is_deleted=0", LLU{parent_id});
 	auto pstmt = gx_sql_prep(psqlite, sql_string);
 	if (pstmt == nullptr)
 		return FALSE;

exch/exmdb_provider/folder.cpp

@@ -315,7 +315,7 @@ BOOL exmdb_server::create_folder_by_properties(const char *dir, cpid_t cpid,
 	}
 	auto qstr = "SELECT 1 FROM folders AS f INNER JOIN folder_properties AS fp "
 	            "ON f.folder_id=fp.folder_id AND fp.proptag=? "
-	            "WHERE f.parent_id=? and fp.propval=? COLLATE NOCASE";
+	            "WHERE f.parent_id=? AND f.is_deleted=0 AND fp.propval=? COLLATE NOCASE";
 	auto pstmt = gx_sql_prep(pdb->psqlite, qstr);
 	if (pstmt == nullptr)
 		return FALSE;