Add dirty_after_edit to SkPath::moveTo. Add commented out test case that triggers assert.

BUG=skia:1460
R=reed@google.com

Author: bsalomon@google.com

Review URL: https://codereview.chromium.org/517023003
diff --git a/src/core/SkPath.cpp b/src/core/SkPath.cpp
index aa7943c..c0049ca 100644
--- a/src/core/SkPath.cpp
+++ b/src/core/SkPath.cpp
@@ -671,6 +671,8 @@
     fLastMoveToIndex = fPathRef->countPoints();
 
     ed.growForVerb(kMove_Verb)->set(x, y);
+
+    DIRTY_AFTER_EDIT;
 }
 
 void SkPath::rMoveTo(SkScalar x, SkScalar y) {