Bug 1124392 - Telemetry: Record the number of passwords per hostname. r=MattN

--HG--
extra : rebase_source : 16de4b58ca570ed7ad328ddc5806eba0a509d9e7

toolkit/components/passwordmgr/nsLoginManager.js

@@ -253,9 +253,13 @@ LoginManager.prototype = {
     let usernamePresentHistogram = clearAndGetHistogram("PWMGR_USERNAME_PRESENT");
     let loginLastUsedDaysHistogram = clearAndGetHistogram("PWMGR_LOGIN_LAST_USED_DAYS");
 
+    let hostnameCount = new Map();
     for (let login of logins) {
       usernamePresentHistogram.add(!!login.username);
 
+      let hostname = login.hostname;
+      hostnameCount.set(hostname, (hostnameCount.get(hostname) || 0 ) + 1);
+
       login.QueryInterface(Ci.nsILoginMetaInfo);
       let timeLastUsedAgeMs = referenceTimeMs - login.timeLastUsed;
       if (timeLastUsedAgeMs > 0) {
@@ -264,6 +268,11 @@ LoginManager.prototype = {
         );
       }
     }
+
+    let passwordsCountHistogram = clearAndGetHistogram("PWMGR_NUM_PASSWORDS_PER_HOSTNAME");
+    for (let count of hostnameCount.values()) {
+      passwordsCountHistogram.add(count);
+    }
   },
 
 

toolkit/components/telemetry/Histograms.json

@@ -7288,6 +7288,13 @@
     "extended_statistics_ok": true,
     "description": "The number of sites for which the user has explicitly rejected saving logins"
   },
+  "PWMGR_NUM_PASSWORDS_PER_HOSTNAME": {
+    "expires_in_version": "never",
+    "kind": "linear",
+    "high": 21,
+    "n_buckets" : 20,
+    "description": "The number of passwords per hostname"
+  },
   "PWMGR_NUM_SAVED_PASSWORDS": {
     "expires_in_version": "never",
     "kind": "exponential",