Remove unowned histograms from HttpStreamFactoryImpl.

tools/metrics/histograms/histograms.xml

Index: tools/metrics/histograms/histograms.xml
diff --git a/tools/metrics/histograms/histograms.xml b/tools/metrics/histograms/histograms.xml
index c681c594f1cfa81a87ba5c27743cb80b21b6aa27..c5eec04516419394c1c5936020b840b3ca5b1848 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -18067,6 +18067,9 @@ Therefore, the affected-histogram name has to have at least one dot in it.
 </histogram>
 
 <histogram name="Net.HttpConnectionLatency" units="milliseconds">
+  <obsolete>
+    Deprecated as of 03/2015.
+  </obsolete>
   <owner>Please list the metric's owners. Add more owner tags as needed.</owner>
   <summary>
     Time between the HttpNetworkTransaction requesting a connection and the time
@@ -18244,6 +18247,9 @@ Therefore, the affected-histogram name has to have at least one dot in it.
 </histogram>
 
 <histogram name="Net.HttpSocketType" enum="HttpSocketType">
+  <obsolete>
+    Deprecated as of 03/2015.
+  </obsolete>
   <owner>Please list the metric's owners. Add more owner tags as needed.</owner>
   <summary>
     The counts of the type of sockets (all HTTP sockets, regardless of any proxy