What happens in this case is that when we analyze this project with
many (very small) files, we successfully index first declarations
(on computing RESOLVED_UNIT3) and then RESOLVED_UNIT. But when we attempt
to search, we ask for RESOLVED_UNIT, which is flushed. So, we compute it.
In the process we compute RESOLVED_UNIT3, and the listener in
_setupIndexInvalidation() indexes declarations, and overwrites the full
index.
There are several possible solutions, the simplest one is to not
overwrite any existing index information while indexing declarations.
R=brianwilkerson@google.com
BUG= https://github.com/dart-lang/sdk/issues/26355
Review URL: https://codereview.chromium.org/1946353004 .
Konstantin Shcheglov
ada9cf43db