Use factory to create histograms, and refcounts to track lifetimes

This is CL patch 377028 by Raman Tenneti, with minor changes to
make the try-bots happier.

It is cleanup that better ensures lifetimes of histograms (making it harder
for users to abuse them).  

bug=16495 (repairs leak induced by the first landing)
bug=18840 (should make leaks less possible)
tbr=raman.tenneti
Review URL: http://codereview.chromium.org/462027

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@33933 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 12 insertions, 10 deletions

diff --git a/net/socket_stream/socket_stream_metrics.cc b/net/socket_stream/socket_stream_metrics.cc
index f7a55a4..6220eb5 100644
--- a/net/socket_stream/socket_stream_metrics.cc
+++ b/net/socket_stream/socket_stream_metrics.cc
@@ -83,19 +83,21 @@ void SocketStreamMetrics::OnClose() {
 }
 
 void SocketStreamMetrics::CountProtocolType(ProtocolType protocol_type) {
-  static LinearHistogram counter("Net.SocketStream.ProtocolType",
-                                 0, NUM_PROTOCOL_TYPES,
-                                 NUM_PROTOCOL_TYPES + 1);
-  counter.SetFlags(kUmaTargetedHistogramFlag);
-  counter.Add(protocol_type);
+  static scoped_refptr<Histogram> counter =
+      LinearHistogram::LinearHistogramFactoryGet(
+          "Net.SocketStream.ProtocolType",
+          0, NUM_PROTOCOL_TYPES, NUM_PROTOCOL_TYPES + 1);
+  counter->SetFlags(kUmaTargetedHistogramFlag);
+  counter->Add(protocol_type);
 }
 
 void SocketStreamMetrics::CountConnectionType(ConnectionType connection_type) {
-  static LinearHistogram counter("Net.SocketStream.ConnectionType",
-                                 1, NUM_CONNECTION_TYPES,
-                                 NUM_CONNECTION_TYPES + 1);
-  counter.SetFlags(kUmaTargetedHistogramFlag);
-  counter.Add(connection_type);
+  static scoped_refptr<Histogram> counter =
+      LinearHistogram::LinearHistogramFactoryGet(
+          "Net.SocketStream.ConnectionType",
+          1, NUM_CONNECTION_TYPES, NUM_CONNECTION_TYPES + 1);
+  counter->SetFlags(kUmaTargetedHistogramFlag);
+  counter->Add(connection_type);
 }