Clean up naming of ShmEventLoop helper classes

Instead of using classes with the same name from multiple namespaces in
the same file, just pick different names for some of them. It's way
easier to read, because the same string always refers to the same thing
throughout the whole file.

Change-Id: I728c74fa1bcf27e7d5882d82e57b31f47510f959
diff --git a/aos/events/shm_event_loop.h b/aos/events/shm_event_loop.h
index 15759f4..f832242 100644
--- a/aos/events/shm_event_loop.h
+++ b/aos/events/shm_event_loop.h
@@ -10,15 +10,15 @@
 #include "aos/events/event_loop_generated.h"
 
 namespace aos {
-namespace internal {
+namespace shm_event_loop_internal {
 
-class WatcherState;
-class TimerHandlerState;
-class PhasedLoopHandler;
+class ShmWatcherState;
+class ShmTimerHandler;
+class ShmPhasedLoopHandler;
 class ShmSender;
 class ShmFetcher;
 
-}  // namespace internal
+}  // namespace shm_event_loop_internal
 
 // Specialization of EventLoop that is built from queues running out of shared
 // memory.
@@ -57,11 +57,10 @@
       std::function<void(const Context &context)> watcher) override;
 
   TimerHandler *AddTimer(std::function<void()> callback) override;
-  aos::PhasedLoopHandler *AddPhasedLoop(
-      std::function<void(int)> callback,
-      const monotonic_clock::duration interval,
-      const monotonic_clock::duration offset =
-          std::chrono::seconds(0)) override;
+  PhasedLoopHandler *AddPhasedLoop(std::function<void(int)> callback,
+                                   const monotonic_clock::duration interval,
+                                   const monotonic_clock::duration offset =
+                                       std::chrono::seconds(0)) override;
 
   void OnRun(std::function<void()> on_run) override;
 
@@ -89,11 +88,11 @@
   }
 
  private:
-  friend class internal::WatcherState;
-  friend class internal::TimerHandlerState;
-  friend class internal::PhasedLoopHandler;
-  friend class internal::ShmSender;
-  friend class internal::ShmFetcher;
+  friend class shm_event_loop_internal::ShmWatcherState;
+  friend class shm_event_loop_internal::ShmTimerHandler;
+  friend class shm_event_loop_internal::ShmPhasedLoopHandler;
+  friend class shm_event_loop_internal::ShmSender;
+  friend class shm_event_loop_internal::ShmFetcher;
 
   static cpu_set_t DefaultAffinity() {
     cpu_set_t result;