Clean up warnings in stubs.cpp.

Change-Id: Ie0792846de7cf5f5c72737494bf78ab8dcb8cc3e

libc/bionic/stubs.cpp

@@ -371,7 +371,8 @@ passwd* getpwnam(const char* login) { // NOLINT: implementing bad function.
   return app_id_to_passwd(app_id_from_name(login), state);
 }
 
-int getgrouplist(const char* user, gid_t group, gid_t* groups, int* ngroups) {
+// All users are in just one group, the one passed in.
+int getgrouplist(const char* /*user*/, gid_t group, gid_t* groups, int* ngroups) {
     if (*ngroups < 1) {
         *ngroups = 1;
         return -1;
@@ -412,51 +413,51 @@ group* getgrnam(const char* name) { // NOLINT: implementing bad function.
   return app_id_to_group(app_id_from_name(name), state);
 }
 
-static void unimplemented_stub(const char* function) {
-  const char* fmt = "%s(3) is not implemented on Android\n";
-  __libc_android_log_print(ANDROID_LOG_WARN, "libc", fmt, function);
-  fprintf(stderr, fmt, function);
+// We don't have an /etc/networks, so all inputs return NULL.
+netent* getnetbyname(const char* /*name*/) {
+  return NULL;
 }
 
-#define UNIMPLEMENTED unimplemented_stub(__PRETTY_FUNCTION__)
-
-netent* getnetbyname(const char* name) {
-  UNIMPLEMENTED;
+// We don't have an /etc/networks, so all inputs return NULL.
+netent* getnetbyaddr(uint32_t /*net*/, int /*type*/) {
   return NULL;
 }
 
-void endpwent() {
-  UNIMPLEMENTED;
+// We don't have an /etc/protocols, so all inputs return NULL.
+protoent* getprotobyname(const char* /*name*/) {
+  return NULL;
 }
 
-mntent* getmntent(FILE* f) {
-  UNIMPLEMENTED;
+// We don't have an /etc/protocols, so all inputs return NULL.
+protoent* getprotobynumber(int /*proto*/) {
   return NULL;
 }
 
-char* ttyname(int fd) { // NOLINT: implementing bad function.
-  UNIMPLEMENTED;
-  return NULL;
+static void unimplemented_stub(const char* function) {
+  const char* fmt = "%s(3) is not implemented on Android\n";
+  __libc_android_log_print(ANDROID_LOG_WARN, "libc", fmt, function);
+  fprintf(stderr, fmt, function);
 }
 
-int ttyname_r(int fd, char* buf, size_t buflen) {
+#define UNIMPLEMENTED unimplemented_stub(__PRETTY_FUNCTION__)
+
+void endpwent() {
   UNIMPLEMENTED;
-  return -ERANGE;
 }
 
-netent* getnetbyaddr(uint32_t net, int type) {
+mntent* getmntent(FILE* /*f*/) {
   UNIMPLEMENTED;
   return NULL;
 }
 
-protoent* getprotobyname(const char* name) {
+char* ttyname(int /*fd*/) { // NOLINT: implementing bad function.
   UNIMPLEMENTED;
   return NULL;
 }
 
-protoent* getprotobynumber(int proto) {
+int ttyname_r(int /*fd*/, char* /*buf*/, size_t /*buflen*/) {
   UNIMPLEMENTED;
-  return NULL;
+  return -ERANGE;
 }
 
 char* getusershell() {