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* Construct more things in the declaration
* Make more things const
* Slightly improve variable names
* Use AddChildView(std::make_unique<...>(...)) idiom for brevity
* Remove various unnecessary setter calls
* Enable auto color readability; set background colors correctly to make
  this work properly; use a solid background for the overall view while
  at it

Bug: none
Change-Id: Ie13ccdb0e620d2f80736daa8a41590a8dfc5116f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2333500
Commit-Queue: Peter Kasting <pkasting@chromium.org>
Reviewed-by: Shakti Sahu <shaktisahu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#795302}