Simplify conversion of quadratic bezier segments
Simplify conversion of quadratic bezier segments

Perform the normalization first, and then compute the control points for
the equivalent cubic segment.

BUG=467592

Review URL: https://codereview.chromium.org/1024583002

git-svn-id: bf5cd6ccde378db821296732a091cfbcf5285fbd@192208 bbb929c8-8fbe-4397-9dbb-9b2b20218538

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