Added of new UMA signals in order to be able to discover early if the "save password" feature gets …

chrome/browser/password_manager/password_manager_delegate_impl.cc

Index: chrome/browser/password_manager/password_manager_delegate_impl.cc
diff --git a/chrome/browser/password_manager/password_manager_delegate_impl.cc b/chrome/browser/password_manager/password_manager_delegate_impl.cc
index f7c42bf88110d2718864d978996f9d8f2010a8d7..a879e8a3c043de58e1f424e94365afa89cae6110 100644
--- a/chrome/browser/password_manager/password_manager_delegate_impl.cc
+++ b/chrome/browser/password_manager/password_manager_delegate_impl.cc
@@ -6,11 +6,14 @@
 
 #include "base/memory/singleton.h"
 #include "base/metrics/histogram.h"
+#include "base/strings/string_number_conversions.h"
 #include "base/strings/utf_string_conversions.h"
+#include "base/test/perftimer.h"
 #include "chrome/browser/infobars/confirm_infobar_delegate.h"
 #include "chrome/browser/infobars/infobar_service.h"
 #include "chrome/browser/password_manager/password_form_manager.h"
 #include "chrome/browser/password_manager/password_manager.h"
+#include "chrome/browser/password_manager/password_manager_metrics_util.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/sync/one_click_signin_helper.h"
 #include "components/autofill/content/browser/autofill_driver_impl.h"
@@ -74,6 +77,14 @@ class SavePasswordInfoBarDelegate : public ConfirmInfoBarDelegate {
   // Used to track the results we get from the info bar.
   ResponseType infobar_response_;
 
+  // Save password prompt lifetime needed for a UMA signal.
+  PerfTimer timer_;
+
+  // The group name corresponding to the domain name of
+  // |form_to_save_| if the form is on a monitored domain.
+  // Otherwise, an empty string.
+  std::string uma_histogram_suffix_;
+
   DISALLOW_COPY_AND_ASSIGN(SavePasswordInfoBarDelegate);
 };
 
@@ -106,11 +117,37 @@ SavePasswordInfoBarDelegate::SavePasswordInfoBarDelegate(
     : ConfirmInfoBarDelegate(infobar_service),
       form_to_save_(form_to_save),
       infobar_response_(NO_RESPONSE) {
+  uma_histogram_suffix_ = password_manager_metrics_util::MonitoredDomainGroup(

[vabr (Chromium), 2013/09/11 17:31:24]

nit: this could be done in the initialiser list:

uma_histogram_suffix_(password_manager_metrics_util::MonitoredDomainGroup(...))

Then you can make uma_histogram_suffix_ a const member variable, improving the
readability and efficiency.

[jdomingos, 2013/09/11 19:15:28]

Done.

+      form_to_save->realm());
+  if (!uma_histogram_suffix_.empty()) {
+    int group_number = 0;
+    std::string string_group_number =
+        uma_histogram_suffix_.substr(uma_histogram_suffix_.find("_") + 1);
+
+    if (!base::StringToInt(string_group_number, &group_number))

[vabr (Chromium), 2013/09/11 17:31:24]

You have just written an int to a string in MonitoredDomainGroup, and here you
parse it back again. Could you get it directly? For example, you can split
MonitoredDomainGroup into the part which gets the number, and the wrapper which
creates the suffix, and call here only the inner part.

[jdomingos, 2013/09/11 19:15:28]

Done.

+      return;
+    password_manager_metrics_util::LogUMAHistogramCounts(
+        "PasswordManager.SavePasswordPromptDisplayed",
+        group_number);
+  }
 }
 
 SavePasswordInfoBarDelegate::~SavePasswordInfoBarDelegate() {
   UMA_HISTOGRAM_ENUMERATION("PasswordManager.InfoBarResponse",
                             infobar_response_, NUM_RESPONSE_TYPES);
+  // Time which allows us to consider that the info bar has been
+  // displayed during enough time for the user to make a decision.

[vabr (Chromium), 2013/09/11 17:31:24]

This is not grammatically correct, and could me more informative.
Suggested rephrasing:

"The shortest period (in ms) for which the prompt needs to
live, so that we don't consider it killed prematurely, as might
happen, e.g., if a pre-rendered page gets swapped in (and the
current WebContent is destroyed)."

[jdomingos, 2013/09/11 19:15:28]

Done.

+  const int kTime = 1000;
+
+  if (!uma_histogram_suffix_.empty()) {
+    password_manager_metrics_util::LogUMAHistogramEnumeration(
+        "PasswordManager.SavePasswordPromptResponse_" + uma_histogram_suffix_,
+        infobar_response_, NUM_RESPONSE_TYPES);
+    password_manager_metrics_util::LogUMAHistogramBoolean(
+        "PasswordManager.SavePasswordPromptDisappearedQuickly" +
+        uma_histogram_suffix_,
+        timer_.Elapsed().InMilliseconds() < kTime);
+  }
 }
 
 int SavePasswordInfoBarDelegate::GetIconID() const {