Improve TakeWatcher error message
We didn't actually say that the reason MakeWatcher fails is because we
already had a sender for that channel on the same event loop
Signed-off-by: milind-u <milind.upadhyay@gmail.com>
Change-Id: I426ca3a67600eb2dcf057d46d97f0c805702edc9
diff --git a/aos/events/event_loop.cc b/aos/events/event_loop.cc
index f5e9f51..c29d820 100644
--- a/aos/events/event_loop.cc
+++ b/aos/events/event_loop.cc
@@ -236,7 +236,8 @@
CHECK(taken_senders_.find(channel) == taken_senders_.end())
<< ": " << configuration::CleanedChannelToString(channel)
- << " is already being used.";
+ << " is already being used for sending. Can't make a watcher on the "
+ "same event loop.";
auto result = taken_watchers_.insert(channel);
CHECK(result.second) << ": " << configuration::CleanedChannelToString(channel)