Add a default implementation in metrics_default.cc of histograms methods in system_wrappers/interfac

webrtc/api/java/jni/classreferenceholder.cc

Index: webrtc/api/java/jni/classreferenceholder.cc
diff --git a/webrtc/api/java/jni/classreferenceholder.cc b/webrtc/api/java/jni/classreferenceholder.cc
index d6c7d567b60662758ba879a908a2992250db7dd6..7073c2d094d40a59123d8ff748ef23f4ac0ccf8f 100644
--- a/webrtc/api/java/jni/classreferenceholder.cc
+++ b/webrtc/api/java/jni/classreferenceholder.cc
@@ -58,6 +58,8 @@ ClassReferenceHolder::ClassReferenceHolder(JNIEnv* jni) {
   LoadClass(jni, "org/webrtc/EglBase");
   LoadClass(jni, "org/webrtc/EglBase$Context");
   LoadClass(jni, "org/webrtc/EglBase14$Context");
+  LoadClass(jni, "org/webrtc/Histograms");
+  LoadClass(jni, "org/webrtc/Histograms$HistogramInfo");
   LoadClass(jni, "org/webrtc/IceCandidate");
   LoadClass(jni, "org/webrtc/MediaCodecVideoEncoder");
   LoadClass(jni, "org/webrtc/MediaCodecVideoEncoder$OutputBufferInfo");