Add metrics to measure time elapsed between form load and form submission with or without Autofill.

chrome/browser/autofill/autofill_metrics.cc

Index: chrome/browser/autofill/autofill_metrics.cc
diff --git a/chrome/browser/autofill/autofill_metrics.cc b/chrome/browser/autofill/autofill_metrics.cc
index c3ad14927d3f8fa9b1d597e4e08a1f2218ec6996..2a7424b384a34cb942887c0973b9d0240133295c 100644
--- a/chrome/browser/autofill/autofill_metrics.cc
+++ b/chrome/browser/autofill/autofill_metrics.cc
@@ -6,6 +6,7 @@
 
 #include "base/logging.h"
 #include "base/metrics/histogram.h"
+#include "base/time.h"
 #include "chrome/browser/autofill/autofill_type.h"
 #include "chrome/browser/autofill/form_structure.h"
 #include "webkit/glue/form_data.h"
@@ -298,6 +299,29 @@ void AutofillMetrics::LogUserHappinessMetric(UserHappinessMetric metric) const {
                             NUM_USER_HAPPINESS_METRICS);
 }
 
+void AutofillMetrics::LogFormFillDurationFromLoadWithAutofill(
+    const base::TimeDelta& duration) const {
+  UMA_HISTOGRAM_TIMES("Autofill.FillDuration.FromLoad.WithAutofill", duration);
+}
+
+void AutofillMetrics::LogFormFillDurationFromLoadWithoutAutofill(
+    const base::TimeDelta& duration) const {
+  UMA_HISTOGRAM_TIMES("Autofill.FillDuration.FromLoad.WithoutAutofill",
+                      duration);
+}
+
+void AutofillMetrics::LogFormFillDurationFromInteractionWithAutofill(
+    const base::TimeDelta& duration) const {
+  UMA_HISTOGRAM_TIMES("Autofill.FillDuration.FromInteraction.WithAutofill",

[jar (doing other things), 2011/09/02 01:48:33]

What is the dynamic range you're expecting for this?  UMA_HISTOGRAM_TIMES has
its overflow bucket start at 10seconds.  Is that too short?  
For instance, UMA_HISTOGRAM_MEDIUM_TIME() runs from 10ms to 3 minutes (and
you'll hopefully make very little use of that tail).

[Ilya Sherman, 2011/09/02 06:57:54]

Oh, wow, good catch!  I think 100ms to 10 minutes is probably a reasonable
dynamic range for this metric -- does my change look correct for that?

[jar (doing other things), 2011/09/02 20:09:26]

Your change to 100ms through 10 minutes looks great.  Thanks.

+                      duration);
+}
+
+void AutofillMetrics::LogFormFillDurationFromInteractionWithoutAutofill(
+    const base::TimeDelta& duration) const {
+  UMA_HISTOGRAM_TIMES("Autofill.FormFillTime.FromInteraction.WithoutAutofill",
+                      duration);
+}
+
 void AutofillMetrics::LogIsAutofillEnabledAtStartup(bool enabled) const {
   UMA_HISTOGRAM_BOOLEAN("Autofill.IsEnabled.Startup", enabled);
 }