Add rect clip to convex_poly_clip GM

src/core/SkTLList.h

Index: src/core/SkTLList.h
diff --git a/src/core/SkTLList.h b/src/core/SkTLList.h
index 298ce516cc01ffa1b0dce0cb872d286730f72ed3..99b5bc67d964d2b6bc07584847993bafff925d71 100644
--- a/src/core/SkTLList.h
+++ b/src/core/SkTLList.h
@@ -75,6 +75,15 @@ public:
         return reinterpret_cast<T*>(node->fObj);
     }
 
+    T* addToHead() {
+        this->validate();
+        Node* node = this->createNode();
+        fList.addToHead(node);
+        SkNEW_PLACEMENT(node->fObj, T);
+        this->validate();
+        return reinterpret_cast<T*>(node->fObj);
+    }
+
     T* addToTail(const T& t) {
         this->validate();
         Node* node = this->createNode();
@@ -84,6 +93,15 @@ public:
         return reinterpret_cast<T*>(node->fObj);
     }
 
+    T* addToTail() {
+        this->validate();
+        Node* node = this->createNode();
+        fList.addToTail(node);
+        SkNEW_PLACEMENT(node->fObj, T);
+        this->validate();
+        return reinterpret_cast<T*>(node->fObj);
+    }
+
     /** Adds a new element to the list before the location indicated by the iterator. If the
         iterator refers to a NULL location then the new element is added at the tail */
     T* addBefore(const T& t, const Iter& location) {