Nest all namespaces

The compiler supports this now.  We can type less going forward.
No functional changes.

Signed-off-by: Stephan Pleines <pleines.stephan@gmail.com>
Change-Id: I29d6fa4f9aacc0e381f1a7637294db0392466995
diff --git a/aos/vision/events/epoll_events.cc b/aos/vision/events/epoll_events.cc
index e417f0d..1a5ad7e 100644
--- a/aos/vision/events/epoll_events.cc
+++ b/aos/vision/events/epoll_events.cc
@@ -10,8 +10,7 @@
 
 #include "aos/logging/logging.h"
 
-namespace aos {
-namespace events {
+namespace aos::events {
 
 void EpollEvent::DirectEvent(uint32_t events) {
   if ((events & ~(EPOLLIN | EPOLLPRI | EPOLLERR)) != 0) {
@@ -72,5 +71,4 @@
   return r;
 }
 
-}  // namespace events
-}  // namespace aos
+}  // namespace aos::events
diff --git a/aos/vision/events/gtk_event.cc b/aos/vision/events/gtk_event.cc
index e1e4e08..7df0716 100644
--- a/aos/vision/events/gtk_event.cc
+++ b/aos/vision/events/gtk_event.cc
@@ -9,8 +9,7 @@
 #include "aos/logging/logging.h"
 #include "aos/vision/events/epoll_events.h"
 
-namespace aos {
-namespace events {
+namespace aos::events {
 
 void EpollLoop::RunWithGtkMain() {
   int timeout;
@@ -69,5 +68,4 @@
   exit(EXIT_SUCCESS);
 }
 
-}  // namespace events
-}  // namespace aos
+}  // namespace aos::events
diff --git a/aos/vision/events/intrusive_free_list.h b/aos/vision/events/intrusive_free_list.h
index 0373741..db096b7 100644
--- a/aos/vision/events/intrusive_free_list.h
+++ b/aos/vision/events/intrusive_free_list.h
@@ -1,8 +1,7 @@
 #ifndef _AOS_VISION_EVENTS_INTRUSIVE_FREE_LIST_H_
 #define _AOS_VISION_EVENTS_INTRUSIVE_FREE_LIST_H_
 
-namespace aos {
-namespace events {
+namespace aos::events {
 
 // Hey! Maybe you want a doubly linked list that frees things for you!
 // This allows the entry to delete itself, removing it from the list, or
@@ -75,7 +74,6 @@
   T *begin_;
 };
 
-}  // namespace events
-}  // namespace aos
+}  // namespace aos::events
 
 #endif  // _AOS_VISION_EVENTS_INTRUSIVE_FREE_LIST_H_
diff --git a/aos/vision/events/tcp_client.cc b/aos/vision/events/tcp_client.cc
index 0a926db..65b646c 100644
--- a/aos/vision/events/tcp_client.cc
+++ b/aos/vision/events/tcp_client.cc
@@ -15,8 +15,7 @@
 
 #include "aos/logging/logging.h"
 
-namespace aos {
-namespace events {
+namespace aos::events {
 
 namespace {
 int MakeSocketNonBlocking(int sfd) {
@@ -63,5 +62,4 @@
 TcpClient::TcpClient(const std::string &hostname, int portno)
     : EpollEvent(OpenClient(hostname, portno)) {}
 
-}  // namespace events
-}  // namespace aos
+}  // namespace aos::events
diff --git a/aos/vision/events/tcp_server.cc b/aos/vision/events/tcp_server.cc
index cf4dd7f..fa2a369 100644
--- a/aos/vision/events/tcp_server.cc
+++ b/aos/vision/events/tcp_server.cc
@@ -16,8 +16,7 @@
 
 #include "aos/logging/logging.h"
 
-namespace aos {
-namespace events {
+namespace aos::events {
 
 namespace {
 
@@ -108,5 +107,4 @@
   loop()->Add(Construct(infd));
 }
 
-}  // namespace events
-}  // namespace aos
+}  // namespace aos::events
diff --git a/aos/vision/events/udp.cc b/aos/vision/events/udp.cc
index 2aaac82..cf7ad23 100644
--- a/aos/vision/events/udp.cc
+++ b/aos/vision/events/udp.cc
@@ -4,8 +4,7 @@
 
 #include "glog/logging.h"
 
-namespace aos {
-namespace events {
+namespace aos::events {
 
 TXUdpSocket::TXUdpSocket(const std::string &ip_addr, int port)
     : fd_(socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) {
@@ -49,5 +48,4 @@
   return result;
 }
 
-}  // namespace events
-}  // namespace aos
+}  // namespace aos::events
diff --git a/aos/vision/events/udp_test.cc b/aos/vision/events/udp_test.cc
index 33fb4d6..506be28 100644
--- a/aos/vision/events/udp_test.cc
+++ b/aos/vision/events/udp_test.cc
@@ -2,8 +2,7 @@
 
 #include "gtest/gtest.h"
 
-namespace aos {
-namespace events {
+namespace aos::events {
 
 TEST(UDPTest, SendRecv) {
   RXUdpSocket rx(1109);
@@ -19,5 +18,4 @@
   EXPECT_EQ(txdata[3], rxdata[3]);
 }
 
-}  // namespace events
-}  // namespace aos
+}  // namespace aos::events