Fix up the clip mask manager's creation of paths (w.r.t. volatility)

src/core/SkClipStack.cpp

Index: src/core/SkClipStack.cpp
diff --git a/src/core/SkClipStack.cpp b/src/core/SkClipStack.cpp
index f54d57fd0ba5f9e8cae84155b43b33af09175ce9..4227eeac68fc8a7b2101422c084966db8414a0d9 100644
--- a/src/core/SkClipStack.cpp
+++ b/src/core/SkClipStack.cpp
@@ -136,14 +136,17 @@ void SkClipStack::Element::asPath(SkPath* path) const {
     switch (fType) {
         case kEmpty_Type:
             path->reset();
+            path->setIsVolatile(true);
             break;
         case kRect_Type:
             path->reset();
             path->addRect(this->getRect());
+            path->setIsVolatile(true);
             break;
         case kRRect_Type:
             path->reset();
             path->addRRect(fRRect);
+            path->setIsVolatile(true);
             break;
         case kPath_Type:
             *path = *fPath.get();