[gparted] Add comment summarising current operation merging rules (#755214)

[Curtis Gedak <gedakc src gnome org>]

commit 27e5bbeeceff47539cbad1a3d228a7a0187c95cb
Author: Mike Fleetwood <mike fleetwood googlemail com>
Date:   Sat Sep 19 09:17:43 2015 +0100

    Add comment summarising current operation merging rules (#755214)
    
    This information is already documented in the existing comments
    associated with the calls to merge_operations() and assignments to the
    mergetype variables.  The table just summaries the rules together in one
    place.
    
    Bug 755214 - Refactor operation merging

 src/Win_GParted.cc |   24 ++++++++++++++++++++++++
 1 files changed, 24 insertions(+), 0 deletions(-)
---
diff --git a/src/Win_GParted.cc b/src/Win_GParted.cc
index 5f03c65..18d642b 100644
--- a/src/Win_GParted.cc
+++ b/src/Win_GParted.cc
@@ -758,6 +758,30 @@ bool Win_GParted::merge_two_operations( unsigned int first, unsigned int second
        return false;
 }
 
+// Try to merge pending operations in the operations[] vector using the specified merge
+// type.
+//
+// Summary of all the operation merging rules for each operation type coded into the
+// ::activate_*() methods:
+//
+// Operation type      Partition status    Merge type             Method
+// -----------------   ----------------    --------------------   -----------------
+// resize/move         Real                MERGE_LAST_WITH_PREV   activate_resize()
+// resize/move         New                 MERGE_LAST_WITH_ANY    activate_resize()
+// paste               *                   none                   activate_paste()
+// new                 *                   none                   activate_new()
+// delete              Real                none                   activate_delete()
+// delete              New                 MERGE_ALL_ADJACENT     activate_delete()
+// format              Real                MERGE_LAST_WITH_PREV   activate_format()
+// format              New                 MERGE_LAST_WITH_ANY    activate_format()
+// check               Real [1]            MERGE_LAST_WITH_ANY    activate_check()
+// label file system   Real [1]            MERGE_LAST_WITH_ANY    activate_label_filesystem()
+// name partition      Real [1]            MERGE_LAST_WITH_ANY    activate_name_partition()
+// new UUID            Real [1]            MERGE_LAST_WITH_ANY    activate_change_uuid()
+//
+// [1] The UI only allows these operations to be applied to real partitions; where as the
+//     other mergeable operations can be applied to both real partitions and new, pending
+//     create partitions.
 void Win_GParted::merge_operations( MergeType mergetype )
 {
        unsigned int num_ops = operations.size();