profiling: use "stat" profiler to profile individual request

The ls profiler no longer works for that. As the lsprof profiler is not default
and not great is general, lets side step the issue for now.

tests/test-profile.t

@@ -50,11 +50,15 In alias
 
 #endif
 
-#if lsprof serve
+#if serve
 
 Profiling of HTTP requests works
 
-  $ prof \
+  $ stats_prof () {
+  >   hg --config profiling.type=stat --profile $@
+  > }
+
+  $ stats_prof \
   >   --config profiling.format=text \
   >   --config profiling.output=../profile.log \
   >  serve -d \
@@ -67,7 +71,9 Profiling of HTTP requests works
   $ cat ../error.log
 
 A single profile is logged because file logging doesn't append
-  $ grep CallCount ../profile.log | wc -l
+  $ grep 'Sample count:' ../profile.log | wc -l
+  \s*1 (re)
+  $ grep 'Total time:' ../profile.log | wc -l
   \s*1 (re)
 
 #endif