Primary histograms for InBrowserCleanerUI experiment

chrome/browser/ui/webui/settings/chrome_cleanup_handler.cc

Index: chrome/browser/ui/webui/settings/chrome_cleanup_handler.cc
diff --git a/chrome/browser/ui/webui/settings/chrome_cleanup_handler.cc b/chrome/browser/ui/webui/settings/chrome_cleanup_handler.cc
index 8965dafa3bec7498abef5948cf508324bb214300..f30940fc8ef99701688b72258ad8ffe040dad97c 100644
--- a/chrome/browser/ui/webui/settings/chrome_cleanup_handler.cc
+++ b/chrome/browser/ui/webui/settings/chrome_cleanup_handler.cc
@@ -8,6 +8,7 @@
 
 #include "base/command_line.h"
 #include "base/feature_list.h"
+#include "base/metrics/histogram_macros.h"
 #include "base/synchronization/lock.h"
 #include "base/values.h"
 #include "chrome/browser/safe_browsing/chrome_cleaner/srt_field_trial_win.h"
@@ -133,6 +134,7 @@ void ChromeCleanupHandler::HandleRegisterChromeCleanerObserver(
   DCHECK(
       base::FeatureList::IsEnabled(safe_browsing::kInBrowserCleanerUIFeature));
 
+  UMA_HISTOGRAM_BOOLEAN("SoftwareReporter.CleanupCardShown", true);

[csharp, 2017/07/07 17:32:51]

It seems odd to have a boolean histogram that is only every marked as true.

Looking at some uma comments, there is UMA_HISTOGRAM_COUNT_*, but the comment
there says if you just want to capture the number of some event, an enum should
be used, ideally with an appropriate baseline.

What about changing this enum to SoftwareReporter.CleanupCard and recording
SHOWN here, and also recording "SHOULD_SHOW" or something like that when users
click more detailed in the prompt.

[1]
https://cs.chromium.org/chromium/src/base/metrics/histogram_macros.h?type=cs&...

[ftirelo, 2017/07/07 20:27:53]

Used a single-value enum instead.

   AllowJavascript();
 }
 
@@ -147,6 +149,8 @@ void ChromeCleanupHandler::HandleRestartComputer(const base::ListValue* args) {
 void ChromeCleanupHandler::HandleStartCleanup(const base::ListValue* args) {
   DCHECK_EQ(0U, args->GetSize());
 
+  safe_browsing::RecordCleanupStartedHistogram(

[csharp, 2017/07/07 17:32:51]

Maybe also worth recording this in the suggested SoftwareReporter.CleanupCard,
to make it easy to see what percentage of people that go to details actually run
the cleanup

[ftirelo, 2017/07/07 20:27:53]

As discussed offline, it will be tricky to do that unless we add a parameter to
the settings page, which is not ideal. We should be able to see the results in a
custom query.

+      safe_browsing::CLEANUP_STARTED_FROM_PROMPT_IN_SETTINGS);
   controller_->ReplyWithUserResponse(
       // TODO(proberge): Send kAcceptedWithLogs or kAcceptedWithoutLogs based on
       // the state of a logs upload permissions checkbox.