Move new convex path towards the end of the path array in GM convexpaths.

Makes triaging a lot easier.

TBR=jvanverth@google.com

Bug: skia:8928
Change-Id: Id800b8e90e94e41c3ce3faaae8f3e10b501f0e04
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/204784
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>

In GrAAConvexPathRenderer check whether middle quadtric control point is close to line segment between first and last control points and if so draw as a line.

Previously we just checked whether the middle control point was close to
either the first or last.

No-Tree-Checks: true
No-Try: true
No-Presubmit: true
Bug: skia:8928
Bug: chromium:945449
Change-Id: I1f7353623c29dcdc329812c44815b80898f83625
Reviewed-On: https://skia-review.googlesource.com/c/skia/+/204981
Reviewed-By: Jim Van Verth <jvanverth@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/205264
Reviewed-by: Brian Salomon <bsalomon@google.com>