Let $D$ be the domain of a twice differentiable function $f$. For all $x \in D, f^{\prime \prime}(x)+f(x)=0$ and $f(x)=\int g(x) d x+$ constant. If $h(x)=\{\mathrm{f}(x)\}^2+\{g(x)\}^2$ and $h(0)=5$, then $h(2015)-h(2014)$ is equal to