Summary:
This commit adds new actions, `applyCategoryToThreads` and `removeCategoryFromThreads`
to be proxied and measured through the ThreadListActionsStore. These are called when
labels are added or removed via the category picker or by removing using
the label icon.
For now, we are only interested in timing actions that remove threads
from the inbox.
Test Plan: manual + reenabled unit tests for category-picker
Reviewers: spang, evan, halla
Reviewed By: halla
Differential Revision: https://phab.nylas.com/D3989
