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, 64 deletions

diff --git a/tests/GeometryTest.cpp b/tests/GeometryTest.cpp
index 5aa80d0b1f..00fc7797dc 100644
--- a/tests/GeometryTest.cpp
+++ b/tests/GeometryTest.cpp
@@ -105,67 +105,6 @@ static void test_conic(skiatest::Reporter* reporter) {
     }
 }
 
-static void test_quad_tangents(skiatest::Reporter* reporter) {
-    SkPoint pts[] = {
-        {10, 20}, {10, 20}, {20, 30},
-        {10, 20}, {15, 25}, {20, 30},
-        {10, 20}, {20, 30}, {20, 30},
-    };
-    int count = (int) SK_ARRAY_COUNT(pts) / 3;
-    for (int index = 0; index < count; ++index) {
-        SkConic conic(&pts[index * 3], 0.707f);
-        SkVector start = SkEvalQuadTangentAt(&pts[index * 3], 0);
-        SkVector mid = SkEvalQuadTangentAt(&pts[index * 3], .5f);
-        SkVector end = SkEvalQuadTangentAt(&pts[index * 3], 1);
-        REPORTER_ASSERT(reporter, start.fX && start.fY);
-        REPORTER_ASSERT(reporter, mid.fX && mid.fY);
-        REPORTER_ASSERT(reporter, end.fX && end.fY);
-        REPORTER_ASSERT(reporter, SkScalarNearlyZero(start.cross(mid)));
-        REPORTER_ASSERT(reporter, SkScalarNearlyZero(mid.cross(end)));
-    }
-}
-
-static void test_conic_tangents(skiatest::Reporter* reporter) {
-    SkPoint pts[] = {
-        { 10, 20}, {10, 20}, {20, 30},
-        { 10, 20}, {15, 25}, {20, 30},
-        { 10, 20}, {20, 30}, {20, 30}
-    };
-    int count = (int) SK_ARRAY_COUNT(pts) / 3;
-    for (int index = 0; index < count; ++index) {
-        SkConic conic(&pts[index * 3], 0.707f);
-        SkVector start = conic.evalTangentAt(0);
-        SkVector mid = conic.evalTangentAt(.5f);
-        SkVector end = conic.evalTangentAt(1);
-        REPORTER_ASSERT(reporter, start.fX && start.fY);
-        REPORTER_ASSERT(reporter, mid.fX && mid.fY);
-        REPORTER_ASSERT(reporter, end.fX && end.fY);
-        REPORTER_ASSERT(reporter, SkScalarNearlyZero(start.cross(mid)));
-        REPORTER_ASSERT(reporter, SkScalarNearlyZero(mid.cross(end)));
-    }
-}
-
-static void test_cubic_tangents(skiatest::Reporter* reporter) {
-    SkPoint pts[] = {
-        { 10, 20}, {10, 20}, {20, 30}, {30, 40},
-        { 10, 20}, {15, 25}, {20, 30}, {30, 40},
-        { 10, 20}, {20, 30}, {30, 40}, {30, 40},
-    };
-    int count = (int) SK_ARRAY_COUNT(pts) / 4;
-    for (int index = 0; index < count; ++index) {
-        SkConic conic(&pts[index * 3], 0.707f);
-        SkVector start, mid, end;
-        SkEvalCubicAt(&pts[index * 4], 0, NULL, &start, NULL);
-        SkEvalCubicAt(&pts[index * 4], .5f, NULL, &mid, NULL);
-        SkEvalCubicAt(&pts[index * 4], 1, NULL, &end, NULL);
-        REPORTER_ASSERT(reporter, start.fX && start.fY);
-        REPORTER_ASSERT(reporter, mid.fX && mid.fY);
-        REPORTER_ASSERT(reporter, end.fX && end.fY);
-        REPORTER_ASSERT(reporter, SkScalarNearlyZero(start.cross(mid)));
-        REPORTER_ASSERT(reporter, SkScalarNearlyZero(mid.cross(end)));
-    }
-}
-
 DEF_TEST(Geometry, reporter) {
     SkPoint pts[3], dst[5];
 
@@ -190,7 +129,4 @@ DEF_TEST(Geometry, reporter) {
     testChopCubic(reporter);
     test_evalquadat(reporter);
     test_conic(reporter);
-    test_cubic_tangents(reporter);
-    test_quad_tangents(reporter);
-    test_conic_tangents(reporter);
 }