Don't coerce pointers to compositor layer mappings to booleans.

Source/core/rendering/CompositedLayerMappingPtr.h

Index: Source/core/rendering/CompositedLayerMappingPtr.h
diff --git a/Source/core/rendering/CompositedLayerMappingPtr.h b/Source/core/rendering/CompositedLayerMappingPtr.h
new file mode 100644
index 0000000000000000000000000000000000000000..540781160529b83e2a23f812473caa400dc0b4d0
--- /dev/null
+++ b/Source/core/rendering/CompositedLayerMappingPtr.h
@@ -0,0 +1,28 @@
+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CompositedLayerMappingPtr_h
+#define CompositedLayerMappingPtr_h
+
+namespace WebCore {
+
+class CompositedLayerMapping;
+
+class CompositedLayerMappingPtr {
+public:
+    CompositedLayerMappingPtr(CompositedLayerMapping* mapping)
+        : m_mapping(mapping)
+    {
+    }
+
+    CompositedLayerMapping& operator*() const { return *m_mapping; }

[shawnsingh, 2013/11/05 10:20:27]

should we ASSERT(m_mapping) here?  I don't feel strongly, but it seems like a
good idea?

[Ian Vollick, 2013/11/08 03:35:12]

Sure, done. I've also added the assert to 'operator->'. We really shouldn't be
using either of these fns if m_mapping is NULL.

+    CompositedLayerMapping* operator->() const { return m_mapping; }
+
+private:
+    CompositedLayerMapping* m_mapping;
+};
+
+} // namespace WebCore
+
+#endif // CompositedLayerMappingPtr_h