Add UMA to break down data usage by http/https and video/non_video

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 cbc2af415e46b6e89b2edfe137c5060f9b031328..478fb52aa6105c2903838c7bbef5de85518ada9c 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -121583,6 +121583,13 @@ from previous Chrome versions.
   <affected-histogram name="Net.RequestTime2.Success"/>
 </histogram_suffixes>
 
+<histogram_suffixes name="NetHttpContentLengthType">

[sclittle, 2017/04/11 20:36:11]

nit: Did you mean to set the separator to "." like the below suffixes block?

[ajo1, 2017/04/11 23:08:49]

I didn't realize you could do that! Changed to '.'

+  <suffix name="Http"/>
+  <suffix name="Https"/>
+  <suffix name="Video"/>
+  <affected-histogram name="Net.HttpContentLength"/>
+</histogram_suffixes>
+
 <histogram_suffixes name="NetHttpProxyConnectLatencySecure" separator=".">
   <owner>tbansal@chromium.org</owner>
   <suffix name="Insecure" label="Insecure proxy"/>