Revert of allow one zero length dash (patchset #8 id:140001 of https://codereview.chromium.org/1805963002/ )

Reason for revert:
Causes the dash bench to crash.

Example crash:
https://build.chromium.org/p/client.skia/builders/Perf-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Release/builds/5581/steps/nanobench/logs/stdio

Original issue's description:
> allow one zero length dash
>
> If the constructed stroke that represents a dash has a
> single dash of length zero, and the end cap is square or
> round, draw the cap.
>
> The old code initialized the initial dash length to zero,
> making it ambiguous whether the first length is zero or
> not.
>
> R=robertphillips@google.com
> BUG=583299
> GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1805963002
>
> Committed: https://skia.googlesource.com/skia/+/5e1a24808415df2748822e8082e21a361362cdfe

TBR=robertphillips@google.com,reed@google.com,caryclark@google.com
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=583299

Review URL: https://codereview.chromium.org/1808303004
6 files changed