Zero-length path with round/square lineCap should paint circle on Canvas

third_party/WebKit/Source/modules/canvas2d/CanvasPathMethods.cpp

 /*
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2010 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2007 Alp Toker <alp@atoker.com>
  * Copyright (C) 2008 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2008 Dirk Schulze <krit@webkit.org>
  * Copyright (C) 2010 Torch Mobile (Beijing) Co. Ltd. All rights reserved.
  * Copyright (C) 2012, 2013 Intel Corporation. All rights reserved.
  * Copyright (C) 2012, 2013 Adobe Systems Incorporated. All rights reserved.
  *
@@ skipping 53 matching lines @@
 void CanvasPathMethods::lineTo(float x, float y)
 {
     if (!std::isfinite(x) || !std::isfinite(y))
         return;
     if (!isTransformInvertible())
         return;
 
     FloatPoint p1 = FloatPoint(x, y);
     if (!m_path.hasCurrentPoint())
         m_path.moveTo(p1);
-    else if (p1 != m_path.currentPoint())
-        m_path.addLineTo(p1);
+
+    m_path.addLineTo(p1);
 }
 
 void CanvasPathMethods::quadraticCurveTo(float cpx, float cpy, float x, float y)
 {
     if (!std::isfinite(cpx) || !std::isfinite(cpy) || !std::isfinite(x) || !std::isfinite(y))
         return;
     if (!isTransformInvertible())
         return;
     if (!m_path.hasCurrentPoint())
         m_path.moveTo(FloatPoint(cpx, cpy));
@@ skipping 230 matching lines @@
         return;
 
     if (!width && !height) {
         m_path.moveTo(FloatPoint(x, y));
         return;
     }
 
     m_path.addRect(FloatRect(x, y, width, height));
 }
 } // namespace blink