RCORE-2212 Make apply-to-state tool handle all batch states properly

[jbreams]

What, How & Why?

☑️ ToDos

• 📝 Changelog update
• 🚦 Tests (or not relevant)
• C-API, if public C++ API changed
• bindgen/spec.yml, if public C++ API changed

[coveralls-official]

Pull Request Test Coverage Report for Build jonathan.reams_3390

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 96 unchanged lines in 21 files lost coverage.
• Overall coverage decreased (-0.01%) to 91.105%

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Files with Coverage Reduction	New Missed Lines	%
src/realm/query_expression.hpp	1	93.81%
src/realm/sort_descriptor.cpp	1	94.06%
src/realm/uuid.cpp	1	98.48%
test/test_index_string.cpp	1	93.48%
test/test_query2.cpp	1	98.73%
src/realm/object-store/shared_realm.cpp	2	91.89%
src/realm/sync/network/http.hpp	2	82.27%
src/realm/table_view.cpp	2	92.99%
test/test_lang_bind_helper.cpp	2	93.2%
src/realm/mixed.cpp	3	86.46%

Totals
Change from base Build 2532:	-0.01%
Covered Lines:	216827
Relevant Lines:	237996

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💛 - Coveralls

[michael-wb]

Do you think we should add a comment to the header for the get_current_protocol_version() function as a reminder to verify the apply_to_state_command tool works with the new protocol version?

[michael-wb]

Is it OK that these changes aren't backwards compatible with sync messages from before sync protocol version 14? I am assuming so, since the history.integrate_server_changesets() function isn't going to work with older messages since it is explicitly looking for the DownloadBatchState::SteadyState value that was introduced in version 14.

Perhaps we should include the get_current_protocol_version() output in the help text to indicate which protocol version "should" be supported?