Add TRACE_EVENT macros to net.

net/http/http_stream_factory_impl_job.cc

Index: net/http/http_stream_factory_impl_job.cc
diff --git a/net/http/http_stream_factory_impl_job.cc b/net/http/http_stream_factory_impl_job.cc
index 82a760c2a536ccb2101fee2614a91f1bf1e7b951..89d193d452335b635591e246e504e2bcd9bfb856 100644
--- a/net/http/http_stream_factory_impl_job.cc
+++ b/net/http/http_stream_factory_impl_job.cc
@@ -21,6 +21,7 @@
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
 #include "base/thread_task_runner_handle.h"
+#include "base/trace_event/trace_event.h"
 #include "base/values.h"
 #include "build/build_config.h"
 #include "net/base/connection_type_histograms.h"
@@ -524,6 +525,7 @@ void HttpStreamFactoryImpl::Job::OnStreamFailedCallback(int result) {
 
 void HttpStreamFactoryImpl::Job::OnCertificateErrorCallback(
     int result, const SSLInfo& ssl_info) {
+  TRACE_EVENT0("net", "HttpStreamFactoryImpl::Job::OnCertificateErrorCallback");

[mmenke, 2016/03/28 20:46:51]

How are you planning on using these?  Seems like basing memory attribution logic
on code like this this would claim something like
"HttpStreamFactoryImpl::Job::OnCertificateErrorCallback" is taking a lot of
memory, while in reality, the problem would be the entire tree of calls below
OnCertificateErrorCallback, none of which involve HttpStreamFactoryImpl::Job. 

[ssid, 2016/03/29 00:33:06]

I agree, in general the answer to your question is: I will try to add tracing
points to more functions in the tree of calls under these function if I know
what are these functions are useful. I am hoping that by these instrumentation,
I can at least understand one more level deeper, if not all the way and tell
what is responsible for memory.

In specific, adding to OnCertificateErrorCallback was a mistake. It does not
give any information, nor the callbacks allocate memory. Sorry. I removed this.

   DCHECK(!IsPreconnecting());
 
   MaybeCopyConnectionAttemptsFromSocketOrHandle();
@@ -606,6 +608,7 @@ void HttpStreamFactoryImpl::Job::OnIOComplete(int result) {
 }
 
 int HttpStreamFactoryImpl::Job::RunLoop(int result) {
+  TRACE_EVENT0("net", "HttpStreamFactoryImpl::Job::RunLoop");
   result = DoLoop(result);
 
   if (result == ERR_IO_PENDING)