Deprecate ConnectionInfo histograms.

ResourceLoader is not used by network service, therefore
Net.HttpResponseInfo.ConnectionInfo.MainFrame and
Net.HttpResponseInfo.ConnectionInfo.SubResource histograms will not be
recorded after network service launches.  This CL obsoletes these two
histograms, and a follow-up CL will add new histograms in the network
service code path.

Bug: 859546
Change-Id: I37e190c1ef060642c08f95314ce52428542a5a2d
Reviewed-on: https://chromium-review.googlesource.com/1122712Reviewed-by: Matt Menke <mmenke@chromium.org>
Reviewed-by: Ilya Sherman <isherman@chromium.org>
Commit-Queue: Bence Béky <bnc@chromium.org>
Cr-Commit-Position: refs/heads/master@{#572174}

content/browser/loader/resource_loader.cc

@@ -832,26 +832,12 @@ void ResourceLoader::CallDidFinishLoading() {
 }
 
 void ResourceLoader::RecordHistograms() {
-  ResourceRequestInfoImpl* info = GetRequestInfo();
-  if (request_->response_info().network_accessed) {
-    if (info->GetResourceType() == RESOURCE_TYPE_MAIN_FRAME) {
-      UMA_HISTOGRAM_ENUMERATION("Net.HttpResponseInfo.ConnectionInfo.MainFrame",
-                                request_->response_info().connection_info,
-                                net::HttpResponseInfo::NUM_OF_CONNECTION_INFOS);
-    } else {
-      UMA_HISTOGRAM_ENUMERATION(
-          "Net.HttpResponseInfo.ConnectionInfo.SubResource",
-          request_->response_info().connection_info,
-          net::HttpResponseInfo::NUM_OF_CONNECTION_INFOS);
-    }
-  }
-
   if (request_->load_flags() & net::LOAD_PREFETCH) {
     // Note that RESOURCE_TYPE_PREFETCH requests are a subset of
     // net::LOAD_PREFETCH requests. In the histograms below, "Prefetch" means
     // RESOURCE_TYPE_PREFETCH and "LoadPrefetch" means net::LOAD_PREFETCH.
     bool is_resource_type_prefetch =
-        info->GetResourceType() == RESOURCE_TYPE_PREFETCH;
+        GetRequestInfo()->GetResourceType() == RESOURCE_TYPE_PREFETCH;
     PrefetchStatus prefetch_status = STATUS_UNDEFINED;
     TimeDelta total_time = base::TimeTicks::Now() - request_->creation_time();
 

tools/metrics/histograms/histograms.xml

@@ -50772,6 +50772,9 @@ uploading your change for review.
 
 <histogram name="Net.HttpResponseInfo.ConnectionInfo.MainFrame"
     enum="ConnectionInfo">
+  <obsolete>
+    Deprecated as of July 2018.
+  </obsolete>
   <owner>mmenke@chromium.org</owner>
   <summary>
     Application protocol used in HTTP responses to requests for main frames.
@@ -50781,6 +50784,9 @@ uploading your change for review.
 
 <histogram name="Net.HttpResponseInfo.ConnectionInfo.SubResource"
     enum="ConnectionInfo">
+  <obsolete>
+    Deprecated as of July 2018.
+  </obsolete>
   <owner>mmenke@chromium.org</owner>
   <summary>
     Application protocol used in HTTP responses to requests for resources other