content: Cleanup GpuMemoryBufferImpl destruction.

content/common/gpu/client/gpu_memory_buffer_impl.cc

Index: content/common/gpu/client/gpu_memory_buffer_impl.cc
diff --git a/content/common/gpu/client/gpu_memory_buffer_impl.cc b/content/common/gpu/client/gpu_memory_buffer_impl.cc
index b3cd98332b41d82eecec0e17434bfb01d865a78d..00a94818b732c971a84deebec29e02612ad35050 100644
--- a/content/common/gpu/client/gpu_memory_buffer_impl.cc
+++ b/content/common/gpu/client/gpu_memory_buffer_impl.cc
@@ -9,12 +9,18 @@
 namespace content {
 
 GpuMemoryBufferImpl::GpuMemoryBufferImpl(const gfx::Size& size,
-                                         unsigned internalformat)
-    : size_(size), internalformat_(internalformat), mapped_(false) {
+                                         unsigned internalformat,
+                                         const DestructionCallback& callback)
+    : size_(size),
+      internalformat_(internalformat),
+      callback_(callback),
+      mapped_(false) {
   DCHECK(IsFormatValid(internalformat));
 }
 
-GpuMemoryBufferImpl::~GpuMemoryBufferImpl() {}
+GpuMemoryBufferImpl::~GpuMemoryBufferImpl() {
+  callback_.Run();
+}
 
 // static
 bool GpuMemoryBufferImpl::IsFormatValid(unsigned internalformat) {