Code completion for default methods in ILog missing in certain situations

If ILog has not yet been used in code, code completion for its default methods does not work.

For example in the eclipse.platform repo I opened `OpenFileMouseHandler` and in line 201 I added ILog and used the quickfix to add the import.

The old log statement is still present, as I still want to copy the existing message to the shorter log API.

I only get the class via code completion.

If I delete the old log statement, code completion starts to work.

This sitational code completion feels broken.

cc @jjohnstn

Reproduce the issue in OpenFileMouseHandler around line 201 in the eclipse.platform repository, keeping the existing log statement while adding ILog. Compare content completion before and after deleting the old statement, then trace the Java editor completion path for ILog default methods. Done means the default methods are offered even when the existing log statement remains.

Written by the indexing model from the issue text.