ApiLint: Add operator keyword and property parsing

Also fix up some issues with expression parsing, type use annotations, etc.

Test: python tools/apilint/apilint_test.py
Change-Id: I38145a51470ce6c3e5813a546d681489fd87fc19
(cherry picked from commit 403c8e35d8e7cc0f81a0a2c42d038c47e1b2703f)
2 files changed