Blueprint compiler doesn't always initialize struct consts correctly

Blueprints currently don't support unsigned 64 bit ints, but they do support signed 64 bits. If a Blueprint uses a native struct variable that contains a uint64 property, it incorrectly assigns that property a value of zero when it's initialized as a constant in the Blueprint bytecode. Instead, it should use whatever value it's currently set to via native code (eg: construct initialization).

1. Download attached project.
2. Build and run the editor
3. Add an instance of TestActor to the level and hit play
4. Output will contain a message like this: LogBlueprintUserMessages: [TestActor_C_UAID_04421AEF787A725F02_1758549879] Title-0000000000000000
5. Stop running and change the data type of MyInnerType::Value to a signed int64
6. Repeat steps 1-2
7. Output will contain a message like this: LogBlueprintUserMessages: [TestActor_C_UAID_04421AEF787A725F02_1369841879] Title-000035B000001F5B

Expected behavior: the first output message should match the second's.