Makes NativeViewport send OnBoundsChanged() after widget available

mojo/public/cpp/bindings/lib/shared_ptr.h

 // Copyright 2014 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 MOJO_PUBLIC_CPP_BINDINGS_LIB_SHARED_PTR_H_
 #define MOJO_PUBLIC_CPP_BINDINGS_LIB_SHARED_PTR_H_
 
 #include "mojo/public/cpp/bindings/lib/shared_data.h"
 
 namespace mojo {
@@ skipping 13 matching lines @@
 
   // Default copy-constructor and assignment operator are OK.
 
   P* get() {
     return impl_.value().ptr;
   }
   const P* get() const {
     return impl_.value().ptr;
   }
 
+  void reset() {
+    impl_.reset();
+  }
+
   P* operator->() { return get(); }
   const P* operator->() const { return get(); }
 
  private:
   class Impl {
    public:
     ~Impl() {
       if (ptr)
         delete ptr;
     }
@@ skipping 10 matching lines @@
     MOJO_DISALLOW_COPY_AND_ASSIGN(Impl);
   };
 
   SharedData<Impl> impl_;
 };
 
 }  // namespace mojo
 }  // namespace internal
 
 #endif  // MOJO_PUBLIC_CPP_BINDINGS_LIB_SHARED_PTR_H_