Core: objects loose label when updating child topics

[jri]

A topic/association looses its label if set() or setRef() is called on its ChildTopics object at a time when both conditions are met:

• The set child topic is not the one used for labeling
• The topic/association's child topics are not loaded (in particular the one(s) involved in labeling)

This bug was introduced with DM 4.4 in conjunction with on-demand child topic loading.

[Jörg Richter <jri@…>]

In cda185daa40ce1eb2c36d8b5f77dfa81bdd1971c/deepamehta:

Add test to illustrate the lost-label issue.

See #766.

[Jörg Richter <jri@…>]

In b9e905d127134ac36c782246f6738c2a23575237/deepamehta:

Core fix: keep label when updating childs (#766).

When calling set() or setRef() on a ChildTopics object the topic/association's label remain intact resp. is properly recalculated in any case.

See #766.

[Jörg Richter <jri@…>]

In 4d49220d40ff9549d8c7ebe930d590607195beb5/deepamehta:

Update lost-label test (#766).

Now the test passes.

See #766.

[Jörg Richter <jri@…>]

In 470291a96fea00c1d6e4e61f7eeb3eb42967dd4f/deepamehta:

Add test: Java's missing multiple dispatch (#766).

See #766.