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- Add more formatting for `code`.
- Fix extra words, etc.
- Fix broken links.
- Add example paths for source code.

This is a documentation-only change.

Change-Id: If7bd21db83762e8547c38e648860c46cfe142fbc
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1846081
Commit-Queue: Darwin Huang <huangdarwin@chromium.org>
Auto-Submit: Darwin Huang <huangdarwin@chromium.org>
Reviewed-by: Oksana Zhuravlova <oksamyt@chromium.org>
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Cr-Commit-Position: refs/heads/master@{#703951}