Fix potential heap data leak in mediadrmserver

                    // data back via the shared buffer rather than

                    // copying it separately over binder to avoid

                    // binder's 1MB limit.

                    memcpy(sharedBuffer->pointer(), dstPtr, totalSize);

                    memcpy(sharedBuffer->pointer(), dstPtr, result);

                }

                free(dstPtr);

                dstPtr = NULL;