Track network stack error codes from UMA and UKM

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 6826f2558c71fc6ddf9c13c1bb1f8333f91d183e..d607f435f271b768083561435c826480ca633d3b 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -72884,6 +72884,12 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   <summary>Number of serialized UKM entries when storing a UKM log.</summary>
 </histogram>
 
+<histogram name="UKM.FailedUploadErrorCode" enum="NetErrorCodes">
+  <owner>holte@chromium.org</owner>
+  <owner>rkaplow@chromium.org</owner>
+  <summary>Net error codes for failed UKM uploads.</summary>
+</histogram>
+
 <histogram name="UKM.InitSequence" enum="UmaInitSequence">
   <owner>holte@chromium.org</owner>
   <owner>rkaplow@chromium.org</owner>
@@ -73211,6 +73217,11 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="UMA.FailedUploadErrorCode" enum="NetErrorCodes">
+  <owner>holte@chromium.org</owner>
+  <summary>Net error codes for failed UMA uploads.</summary>
+</histogram>
+
 <histogram name="UMA.FieldTrialAllocator.Size" units="bytes">
   <obsolete>
     Deprecated 11/2016 for UMA.FieldTrialAllocator.Used