Fix memtrack_helper for newer versions Android.

tools/android/memtrack_helper/memtrack_helper.h

 /*
  * Copyright 2015 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 TOOLS_ANDROID_MEMTRACK_HELPER_H_
 #define TOOLS_ANDROID_MEMTRACK_HELPER_H_
 
 #include <android/log.h>
 #include <errno.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <sys/socket.h>
 #include <sys/un.h>
+#include <unistd.h>
 
 static inline void exit_with_failure(const char* reason) {
   perror(reason);
   __android_log_write(ANDROID_LOG_ERROR, "memtrack_helper", reason);
   exit(EXIT_FAILURE);
 }
 
 static inline void init_memtrack_server_addr(struct sockaddr_un* addr) {
   const char* const kAbstractSocketName = "chrome_tracing_memtrack_helper";
   memset(addr, 0, sizeof(*addr));
   addr->sun_family = AF_UNIX;
   strncpy(&addr->sun_path[1], kAbstractSocketName, sizeof(addr->sun_path) - 2);
 }
 
+static inline void log_pid() {

[Primiano Tucci (use gerrit), 2016/12/14 15:51:16]

This is used only in one place, only in the .cc file.
Just add those lines there.
The deal with this file was to share code between the damon and the test client.

[kraynov, 2016/12/15 15:43:48]

Done.

+  long pid = getpid();
+  fprintf(stderr, "pid=%ld\n", pid);
+  __android_log_print(ANDROID_LOG_INFO, "memtrack_helper", "pid=%ld\n", pid);
+}
+
 #endif  // TOOLS_ANDROID_MEMTRACK_HELPER_H_