Revert of fix zero-length tangent (patchset #2 id:20001 of https://codereview.chromium.org/1311273002/ )

Reason for revert:
causes layout test to draw differently -- new drawing is more correct. Reverting until layout test ignore is landed.

Original issue's description:
> fix zero-length tangent
>
> If the end point and the control point are the same, computing
> the tangent will result in (0, 0). In this case, use the prior
> control point instead.
>
> R=reed@google.com
>
> BUG=skia:4191
>
> Committed: https://skia.googlesource.com/skia/+/7544124fb8ee744f68f549a353f8a9163cd7432d

TBR=reed@google.com
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=skia:4191

Review URL: https://codereview.chromium.org/1312243002

1 files changed, 0 insertions, 56 deletions

diff --git a/gm/strokes.cpp b/gm/strokes.cpp
index 0bcb039783..73823907a3 100644
--- a/gm/strokes.cpp
+++ b/gm/strokes.cpp
@@ -266,60 +266,6 @@ private:
     typedef skiagm::GM INHERITED;
 };
 
-// Test stroking for curves that produce degenerate tangents when t is 0 or 1 (see bug 4191)
-class Strokes5GM : public skiagm::GM {
-public:
-    Strokes5GM() {}
-
-protected:
-
-    SkString onShortName() override {
-        return SkString("zero_control_stroke");
-    }
-
-    SkISize onISize() override {
-        return SkISize::Make(W, H*2);
-    }
-
-    void onDraw(SkCanvas* canvas) override {
-        SkPaint p;
-        p.setColor(SK_ColorRED);
-        p.setAntiAlias(true);
-        p.setStyle(SkPaint::kStroke_Style);
-        p.setStrokeWidth(40);
-        p.setStrokeCap(SkPaint::kButt_Cap);
-
-        SkPath path;
-        path.moveTo(157.474f,111.753f);
-        path.cubicTo(128.5f,111.5f,35.5f,29.5f,35.5f,29.5f);
-        canvas->drawPath(path, p);
-        path.reset();
-        path.moveTo(250, 50);
-        path.quadTo(280, 80, 280, 80);
-        canvas->drawPath(path, p);
-        path.reset();
-        path.moveTo(150, 50);
-        path.conicTo(180, 80, 180, 80, 0.707f);
-        canvas->drawPath(path, p);
-
-        path.reset();
-        path.moveTo(157.474f,311.753f);
-        path.cubicTo(157.474f,311.753f,85.5f,229.5f,35.5f,229.5f);
-        canvas->drawPath(path, p);
-        path.reset();
-        path.moveTo(280, 250);
-        path.quadTo(280, 250, 310, 280);
-        canvas->drawPath(path, p);
-        path.reset();
-        path.moveTo(180, 250);
-        path.conicTo(180, 250, 210, 280, 0.707f);
-        canvas->drawPath(path, p);
-    }
-
-private:
-    typedef skiagm::GM INHERITED;
-};
-
 
 //////////////////////////////////////////////////////////////////////////////
 
@@ -327,10 +273,8 @@ static skiagm::GM* F0(void*) { return new StrokesGM; }
 static skiagm::GM* F1(void*) { return new Strokes2GM; }
 static skiagm::GM* F2(void*) { return new Strokes3GM; }
 static skiagm::GM* F3(void*) { return new Strokes4GM; }
-static skiagm::GM* F4(void*) { return new Strokes5GM; }
 
 static skiagm::GMRegistry R0(F0);
 static skiagm::GMRegistry R1(F1);
 static skiagm::GMRegistry R2(F2);
 static skiagm::GMRegistry R3(F3);
-static skiagm::GMRegistry R4(F4);