Add histogram for printer status reasons

This changes adds metrics to record the printer status reasons returned
by printer status queries. This metric coincides with the addition of
printer availability icons to the Print Preview destination dropdown
(go/printer-status-design-doc).

Bug: 1059607
Change-Id: Ica85163a3dcc0ecdbe34370f14f998512aaa3a4e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2347313
Reviewed-by: Zentaro Kavanagh <zentaro@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>
Reviewed-by: Bailey Berro <baileyberro@chromium.org>
Reviewed-by: Ilya Sherman <isherman@chromium.org>
Commit-Queue: Gavin Williams <gavinwill@chromium.org>
Cr-Commit-Position: refs/heads/master@{#797789}

chrome/browser/chromeos/printing/cups_printers_manager.cc

@@ -425,6 +425,14 @@ class CupsPrintersManagerImpl
         break;
       }
       case PrinterQueryResult::SUCCESS: {
+        // Record results from PrinterStatus before converting to
+        // CupsPrinterStatus because the PrinterStatus enum contains more reason
+        // buckets.
+        for (const auto& reason : printer_status.reasons) {
+          base::UmaHistogramEnumeration("Printing.CUPS.PrinterStatusReasons",
+                                        reason.reason);
+        }
+
         // Convert printing::PrinterStatus to printing::CupsPrinterStatus
         CupsPrinterStatus cups_printers_status =
             PrinterStatusToCupsPrinterStatus(printer_id, printer_status);

printing/printer_status.h

@@ -18,7 +18,9 @@ namespace printing {
 // printer-state-reasons, and printer-state-message.
 struct PRINTING_EXPORT PrinterStatus {
   struct PrinterReason {
-    // Standardized reasons from RFC2911.
+    // This enum is used to record UMA histogram values and should not be
+    // reordered. Please keep in sync with PrinterStatusReasons in
+    // src/tools/metrics/histograms/enums.xml.
     enum class Reason {
       UNKNOWN_REASON = 0,
       NONE = 1,
@@ -53,7 +55,8 @@ struct PRINTING_EXPORT PrinterStatus {
       OPC_LIFE_OVER = 30,
       DEVELOPER_LOW = 31,
       DEVELOPER_EMPTY = 32,
-      INTERPRETER_RESOURCE_UNAVAILABLE = 33
+      INTERPRETER_RESOURCE_UNAVAILABLE = 33,
+      kMaxValue = INTERPRETER_RESOURCE_UNAVAILABLE
     };
 
     // Severity of the state-reason.

tools/metrics/histograms/enums.xml

@@ -57324,6 +57324,43 @@ Called by update_net_trust_anchors.py.-->
   <int value="4" label="Printer was setup via Extensions API"/>
 </enum>
 
+<enum name="PrinterStatusReasons">
+  <int value="0" label="UNKNOWN_REASON"/>
+  <int value="1" label="NONE"/>
+  <int value="2" label="MEDIA_NEEDED"/>
+  <int value="3" label="MEDIA_JAM"/>
+  <int value="4" label="MOVING_TO_PAUSED"/>
+  <int value="5" label="PAUSED"/>
+  <int value="6" label="SHUTDOWN"/>
+  <int value="7" label="CONNECTING_TO_DEVICE"/>
+  <int value="8" label="TIMED_OUT"/>
+  <int value="9" label="STOPPING"/>
+  <int value="10" label="STOPPED_PARTLY"/>
+  <int value="11" label="TONER_LOW"/>
+  <int value="12" label="TONER_EMPTY"/>
+  <int value="13" label="SPOOL_AREA_FULL"/>
+  <int value="14" label="COVER_OPEN"/>
+  <int value="15" label="INTERLOCK_OPEN"/>
+  <int value="16" label="DOOR_OPEN"/>
+  <int value="17" label="INPUT_TRAY_MISSING"/>
+  <int value="18" label="MEDIA_LOW"/>
+  <int value="19" label="MEDIA_EMPTY"/>
+  <int value="20" label="OUTPUT_TRAY_MISSING"/>
+  <int value="21" label="OUTPUT_AREA_ALMOST_FULL"/>
+  <int value="22" label="OUTPUT_AREA_FULL"/>
+  <int value="23" label="MARKER_SUPPLY_LOW"/>
+  <int value="24" label="MARKER_SUPPLY_EMPTY"/>
+  <int value="25" label="MARKER_WASTE_ALMOST_FULL"/>
+  <int value="26" label="MARKER_WASTE_FULL"/>
+  <int value="27" label="FUSER_OVER_TEMP"/>
+  <int value="28" label="FUSER_UNDER_TEMP"/>
+  <int value="29" label="OPC_NEAR_EOL"/>
+  <int value="30" label="OPC_LIFE_OVER"/>
+  <int value="31" label="DEVELOPER_LOW"/>
+  <int value="32" label="DEVELOPER_EMPTY"/>
+  <int value="33" label="INTERPRETER_RESOURCE_UNAVAILABLE"/>
+</enum>
+
 <enum name="PrintJobResult">
   <int value="0" label="Unknown"/>
   <int value="1" label="Successful Finish"/>

tools/metrics/histograms/histograms.xml

@@ -139380,6 +139380,18 @@ reviews. Googlers can read more about this at go/gwsq-gerrit.
   </summary>
 </histogram>
 
+<histogram name="Printing.CUPS.PrinterStatusReasons"
+    enum="PrinterStatusReasons" expires_after="2021-08-10">
+  <owner>gavinwill@chromium.org</owner>
+  <owner>cros-peripherals@google.com</owner>
+  <summary>
+    Records the status reasons returned by a local printer from a printer status
+    query. Each returned printer status request can contain multiple status
+    reasons so summing these buckets will overcount the total # of status
+    queries.
+  </summary>
+</histogram>
+
 <histogram name="Printing.CUPS.PrintJobDatabaseEntries" units="entries"
     expires_after="2020-09-11">
   <owner>nikitapodguzov@chromium.org</owner>