Bug 1013448 (part 1) - add telemetry probe for master-password usage. r=dolske

browser/base/content/browser.js

@@ -1207,6 +1207,16 @@ var gBrowserInit = {
       SocialUI.init();
       TabView.init();
     });
+
+    // telemetry for master-password
+    let secmodDB = Cc["@mozilla.org/security/pkcs11moduledb;1"].
+                   getService(Ci.nsIPKCS11ModuleDB);
+    let slot = secmodDB.findSlotByName("");
+    let mpEnabled = slot &&
+                    slot.status != Ci.nsIPKCS11Slot.SLOT_UNINITIALIZED &&
+                    slot.status != Ci.nsIPKCS11Slot.SLOT_READY;
+    Services.telemetry.getHistogramById("MASTER_PASSWORD_ENABLED").add(mpEnabled);
+
     this.delayedStartupFinished = true;
 
     Services.obs.notifyObservers(window, "browser-delayed-startup-finished", "");

toolkit/components/telemetry/Histograms.json

@@ -6072,5 +6072,10 @@
     "kind": "enumerated",
     "n_values": 512,
     "description": "Certificate pinning test results by host for Mozilla operational sites"
+  },
+  "MASTER_PASSWORD_ENABLED": {
+    "expires_in_version": "never",
+    "kind": "boolean",
+    "description": "If a master-password is enabled for this profile"
   }
 }