Create histograms to track time-to-error values for different errors.

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 7b6aba272ebb8407ff7973bc288f66d54e635ae6..4d07ced3489ed58de659d016f0f0c1a421d231df 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -21155,6 +21155,62 @@ Therefore, the affected-histogram name has to have at least one dot in it.
   </summary>
 </histogram>
 
+<histogram name="Net.RequestTime.ErrAborted">
+  <owner>rdsmith@chromium.org</owner>
+  <summary>
+    The amount of time between request initiation and request abort, for aborted
+    main frame requests.
+  </summary>
+</histogram>
+
+<histogram name="Net.RequestTime.ErrConnectionReset">
+  <owner>rdsmith@chromium.org</owner>
+  <summary>
+    The amount of time between request initiation and connection reset, for main
+    frame requests which end in connection reset.
+  </summary>
+</histogram>
+
+<histogram name="Net.RequestTime.ErrConnectionTimedOut">
+  <owner>rdsmith@chromium.org</owner>
+  <summary>
+    The amount of time between request initiation and connection timeout, for
+    main frame requests which end in connection reset.
+  </summary>
+</histogram>
+
+<histogram name="Net.RequestTime.ErrInternetDisconnected">
+  <owner>rdsmith@chromium.org</owner>
+  <summary>
+    The amount of time between request initiation and internet disconnected, for
+    main frame requests which end in internet disconnected.
+  </summary>
+</histogram>
+
+<histogram name="Net.RequestTime.ErrTimedOut">
+  <owner>rdsmith@chromium.org</owner>
+  <summary>
+    The amount of time between request initiation and request timeout, for timed
+    out main frame requests.
+  </summary>
+</histogram>
+
+<histogram name="Net.RequestTime.MiscError">
+  <owner>rdsmith@chromium.org</owner>
+  <summary>
+    The amount of time between request initiation and error detection, for main
+    frame requests which end in an error not otherwise logged.
+  </summary>
+</histogram>
+
+<histogram name="Net.RequestTime.Success">
+  <owner>rdsmith@chromium.org</owner>
+  <summary>
+    The amount of time between request initiation and reading the last response
+    byte from the network, for successful main frame requests.
+  </summary>
+</histogram>
+
 <histogram name="Net.ResourceLoader.ReadDeferral" units="milliseconds">
   <owner>clamy@chromium.org</owner>
   <summary>