Add unit test to feed valid SVG sequences to make sure that
path strings can be parsed without returning an error.

Draw the output through Skia and SVG to make sure they are
parsed correctly.

R=fmalita@chromium.org
BUG=skia:4549
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1675053002

Review URL: https://codereview.chromium.org/1675053002
diff --git a/src/core/SkPath.cpp b/src/core/SkPath.cpp
index f3c2628..dcc3e02 100644
--- a/src/core/SkPath.cpp
+++ b/src/core/SkPath.cpp
@@ -1265,6 +1265,7 @@
 // Note that arcSweep bool value is flipped from the original implementation.
 void SkPath::arcTo(SkScalar rx, SkScalar ry, SkScalar angle, SkPath::ArcSize arcLarge,
                    SkPath::Direction arcSweep, SkScalar x, SkScalar y) {
+    this->injectMoveToIfNeeded();
     SkPoint srcPts[2];
     this->getLastPt(&srcPts[0]);
     // If rx = 0 or ry = 0 then this arc is treated as a straight line segment (a "lineto")