* src/engine/app/app-conversation-monitor.vala (ConversationMonitor):
Don't check the folder blacklist for external folder signals when the
signal is received, do it when the operation is executed so it's fresh.
* src/engine/app/conversation-monitor/app-fill-window-operation.vala
(FillWindowOperation): Only re-fill the conversation if we get a full
load, anything else means we hit the end of the folder.
* test/engine/app/app-conversation-monitor-test.vala: New unit tests
for ConversationMonitor.
* test/engine/api/geary-account-mock.vala,
test/engine/api/geary-folder-mock.vala: Mix in MockObject mock up all
method calls.
* test/engine/api/geary-email-identifier-mock.vala: Fix the comparator
method when the other instance is null.
3bf2ac181a