Revert "libprocessgroup: Remove __BEGIN_DECLS and __END_DECLS"

This reverts commit fdf4432356ddb597f46cfb7b047ab4e0bb808ba2.

Reason for revert: b/379796721

Change-Id: I34cdc69d5b8d11446da02106b7bd593a8c8151c3
diff --git a/libprocessgroup/include/processgroup/processgroup.h b/libprocessgroup/include/processgroup/processgroup.h
index 6a026a7..d27b568 100644
--- a/libprocessgroup/include/processgroup/processgroup.h
+++ b/libprocessgroup/include/processgroup/processgroup.h
@@ -16,6 +16,7 @@
 
 #pragma once
 
+#include <sys/cdefs.h>
 #include <sys/types.h>
 #include <initializer_list>
 #include <span>
@@ -23,6 +24,8 @@
 #include <string_view>
 #include <vector>
 
+__BEGIN_DECLS
+
 static constexpr std::string CGROUPV2_HIERARCHY_NAME = "cgroup2";
 
 bool CgroupsAvailable();
@@ -36,6 +39,8 @@
 bool SetProcessProfiles(uid_t uid, pid_t pid, const std::vector<std::string>& profiles);
 bool SetUserProfiles(uid_t uid, const std::vector<std::string>& profiles);
 
+__END_DECLS
+
 bool SetTaskProfiles(pid_t tid, std::initializer_list<std::string_view> profiles,
                      bool use_fd_cache = false);
 bool SetProcessProfiles(uid_t uid, pid_t pid, std::initializer_list<std::string_view> profiles);
@@ -45,6 +50,7 @@
 bool SetProcessProfiles(uid_t uid, pid_t pid, std::span<const std::string_view> profiles);
 #endif
 
+__BEGIN_DECLS
 
 #ifndef __ANDROID_VNDK__
 
@@ -90,3 +96,5 @@
 bool isProfileValidForProcess(const std::string& profile_name, uid_t uid, pid_t pid);
 
 #endif // __ANDROID_VNDK__
+
+__END_DECLS