Add metrics to printer setup flow.

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 d8fc24dd8132ed6f866e1d1d61cceb35169a3453..0e646bcb75b79f95d35c86f7f72a2410793d0d06 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -57090,6 +57090,15 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="Printing.CUPS.PpdSource" enum="PpdSource">
+  <owner>skau@chromium.org</owner>
+  <summary>
+    Records the source of PostScript Printer Description files used during
+    printer setup.  Entries are recorded for every attempted configuration. Only
+    recorded on Chrome OS.
+  </summary>
+</histogram>
+
 <histogram name="Printing.CUPS.PrintersDiscovered" units="printers">
   <owner>skau@chromium.org</owner>
   <summary>
@@ -57098,6 +57107,15 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="Printing.CUPS.PrinterSetupResult" enum="PrinterSetupResult">
+  <owner>skau@chromium.org</owner>
+  <summary>
+    The success or error code for the setup of a CUPS printer.  Recorded when
+    setup is attempted through the settings dialogs.  Only recorded on Chrome
+    OS.
+  </summary>
+</histogram>
+
 <histogram name="Printing.CUPS.PrintJobsQueued" units="count">
   <owner>skau@chromium.org</owner>
   <summary>