Revert of experiment with zero-length round capped line segments

Revert of experiment with zero-length round capped line segments (patchset #4 id:60001 of https://codereview.chromium.org/1309753002/ )

Reason for revert:
More GMs changed than I expected. Will probably affect layout tests as well; reverting until I can verify that the changes are correct.

Original issue's description:
> experiment with zero-length round capped line segments
> 
> If the endcap is not butt, draw the endcaps even when the line
> has zero length.
> 
> If the dash length is zero, generate a zero length line segment.
> 
> Treat a move followed by a close as a move followed by a zero-length
> line.
> 
> R=reed@google.com,schenney@google.com
> BUG=422974
> 
> Committed: https://skia.googlesource.com/skia/+/dd3c165828fffb369d0f4b13b48381169a0249a9

TBR=reed@google.com,schenney@google.com,schenney@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=422974
Committed: https://skia.googlesource.com/skia/+/21b998b181bedcd92c3a0460d29492312c0cdc89

[caryclark, 2015-08-21 20:46:45]

Created Revert of experiment with zero-length round capped line segments

[commit-bot: I haz the power, 2015-08-21 20:47:02]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1304163008/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1304163008/1

[commit-bot: I haz the power, 2015-08-21 20:47:09]

Committed patchset #1 (id:1) as
https://skia.googlesource.com/skia/+/21b998b181bedcd92c3a0460d29492312c0cdc89

[caryclark, 2015-08-26 14:19:37]

A revert of this CL (patchset #1 id:1) has been created in
https://codereview.chromium.org/1305313005/ by caryclark@google.com.

The reason for reverting is: Suppressed layout tests that are changed; verified
that GM changes are correct.