Strip out stream counting from AudioRendererHost.

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 3b8e235c0d3a43aeb97dc7d676855ac4cd9e0314..1df6261ba70882387499f38a63dcc5f2d14b620d 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -24865,6 +24865,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="Media.AudioRendererIpcStreams">
+  <obsolete>
+    Deprecated 02/2017. No longer needed.
+  </obsolete>
   <owner>grunell@chromium.org</owner>
   <summary>
     The maximum number of simultaneous audio render streams over IPC created in
@@ -24873,6 +24876,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="Media.AudioRendererIpcStreamsTotal">
+  <obsolete>
+    Deprecated 02/2017. No longer needed.
+  </obsolete>
   <owner>grunell@chromium.org</owner>
   <summary>
     The maximum number of simultaneous audio render streams over IPC created in