Add macros and APIs for webrtc histograms.
BUG=crbug/419657
Code that links system_wrappers.gyp:system_wrappers should either:
- provide implementations for the APIs, or
- link with default implementations in system_wrappers.gyp:system_wrappers_default.
R=andresp@webrtc.org, kjellander@webrtc.org, mflodman@webrtc.org
Review URL: https://webrtc-codereview.appspot.com/22809004
git-svn-id: http://webrtc.googlecode.com/svn/trunk@7508 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/webrtc/system_wrappers/source/metrics_default.cc b/webrtc/system_wrappers/source/metrics_default.cc
new file mode 100644
index 0000000..af950b4
--- /dev/null
+++ b/webrtc/system_wrappers/source/metrics_default.cc
@@ -0,0 +1,29 @@
+// Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the LICENSE file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+//
+
+#include "webrtc/system_wrappers/interface/metrics.h"
+
+// Default implementation of histogram methods for WebRTC clients that do not
+// want to provide their own implementation.
+
+namespace webrtc {
+namespace metrics {
+
+Histogram* HistogramFactoryGetCounts(const std::string& name, int min, int max,
+ int bucket_count) { return NULL; }
+
+Histogram* HistogramFactoryGetEnumeration(const std::string& name,
+ int boundary) { return NULL; }
+
+void HistogramAdd(
+ Histogram* histogram_pointer, const std::string& name, int sample) {}
+
+} // namespace metrics
+} // namespace webrtc
+
