R1:6a13b3ea7e82

Separate the inline comment summary element into a separate view

Summary:
- Affects the "Inline Comments" summary table which appears in comments that have attached inlines in the discussion threads in Differential.
- Prepares for inclusion in Diffusion.
- No application changes (minor CSS), just factors code better.
- Simplify/separate CSS.

Test Plan: Looked at on-diff and off-diff comment summaries in Differential, display looked correct.

Reviewers: davidreuss, nh, btrahan

Reviewed By…