servicemanager: remove pre-4.4 pidcon path

setRequestingSid was added since kernel version 4.4, so
we should no longer need it.

Bug: 376122465
Test: boot
Change-Id: I1ebc04570aae6a441f3a37103b50815514aa6a57
diff --git a/cmds/servicemanager/Access.cpp b/cmds/servicemanager/Access.cpp
index 8098724..6e2abf6 100644
--- a/cmds/servicemanager/Access.cpp
+++ b/cmds/servicemanager/Access.cpp
@@ -34,7 +34,9 @@
 
 #ifdef __ANDROID__
 static std::string getPidcon(pid_t pid) {
-    android_errorWriteLog(0x534e4554, "121035042");
+    CHECK_EQ(nullptr, IPCThreadState::self()->getServingStackPointer())
+            << "Did not get context from PID " << pid
+            << ". We should always get contexts from other processes.";
 
     char* lookup = nullptr;
     if (getpidcon(pid, &lookup) < 0) {