Bug 1392951 - Implement telemetry probe for home page setup. r=liuche,mconley

- Send a ping when user type in "Home page" box.
  - String is longer than 4 letters and with at least one ".".
  - String is not deleted after 3 seconds.
- Send a ping when "Use Current Page" is clicked.
- Send a ping when "Use Bookmark" is clicked.
- Send the number of "|" is detected in "Home page" box.

MozReview-Commit-ID: 6bYK0eCkYym

--HG--
extra : rebase_source : 8ead54eff6e34fb8cc33d8a0a9d463902ed534e7

browser/components/preferences/in-content/main.js

@@ -299,6 +299,8 @@ var gMainPane = {
       gMainPane.checkBrowserContainers);
     setEventListener("browserContainersSettings", "command",
       gMainPane.showContainerSettings);
+    setEventListener("browserHomePage", "input",
+      gMainPane.onBrowserHomePageChange);
 
     // Initializes the fonts dropdowns displayed in this pane.
     this._rebuildFonts();
@@ -743,8 +745,11 @@ var gMainPane = {
     }
 
     // FIXME Bug 244192: using dangerous "|" joiner!
-    if (tabs.length)
+    if (tabs.length) {
       homePage.value = tabs.map(getTabURI).join("|");
+    }
+
+    Services.telemetry.scalarAdd("preferences.use_current_page", 1);
   },
 
   /**
@@ -757,6 +762,23 @@ var gMainPane = {
     gSubDialog.open("chrome://browser/content/preferences/selectBookmark.xul",
       "resizable=yes, modal=yes", rv,
       this._setHomePageToBookmarkClosed.bind(this, rv));
+    Services.telemetry.scalarAdd("preferences.use_bookmark", 1);
+  },
+
+  onBrowserHomePageChange() {
+    if (this.telemetryHomePageTimer) {
+      clearTimeout(this.telemetryHomePageTimer);
+    }
+    let browserHomePage = document.querySelector("#browserHomePage").value;
+    // The length of the home page URL string should be more then four,
+    // and it should contain at least one ".", for example, "https://mozilla.org".
+    if (browserHomePage.length > 4 && browserHomePage.includes(".")) {
+      this.telemetryHomePageTimer = setTimeout(() => {
+        let homePageNumber = browserHomePage.split("|").length;
+        Services.telemetry.scalarAdd("preferences.browser_home_page_change", 1);
+        Services.telemetry.keyedScalarAdd("preferences.browser_home_page_count", homePageNumber, 1);
+      }, 3000);
+    }
   },
 
   _setHomePageToBookmarkClosed(rv, aEvent) {

toolkit/components/telemetry/Scalars.yaml

@@ -545,6 +545,64 @@ preferences:
     release_channel_collection: opt-in
     record_in_processes:
       - main
+  browser_home_page_change:
+    bug_numbers:
+      - 1392951
+    description: >-
+      The number of times the home page has been changed.
+      Recorded when a user changes his/her home page successfully.
+    expires: "62"
+    kind: uint
+    keyed: true
+    notification_emails:
+      - chsiang@mozilla.com
+    release_channel_collection: opt-out
+    record_in_processes:
+      - main
+  browser_home_page_count:
+    bug_numbers:
+      - 1392951
+    description: >-
+      Each key is the number of home page urls when users change their home page,
+      multiple home pages can be set (delineated with a "|"),
+      and each value is the number of times that key is recorded.
+      The telemetry data will be recorded if a user changes his/her home page successfully.
+    expires: "62"
+    kind: uint
+    keyed: true
+    notification_emails:
+      - chsiang@mozilla.com
+    release_channel_collection: opt-out
+    record_in_processes:
+      - main
+  use_current_page:
+    bug_numbers:
+      - 1392951
+    description: >-
+      The number of times the Use Current Page button has been clicked.
+      Recorded when a a user clicks the "Use Current Page" button.
+    expires: "62"
+    kind: uint
+    keyed: true
+    notification_emails:
+      - chsiang@mozilla.com
+    release_channel_collection: opt-out
+    record_in_processes:
+      - main
+  use_bookmark:
+    bug_numbers:
+      - 1392951
+    description: >-
+      The number of times the "Use Bookmark..." button has been clicked.
+      Recorded when a a user clicks the "Use Bookmark..." button.
+    expires: "62"
+    kind: uint
+    keyed: true
+    notification_emails:
+      - chsiang@mozilla.com
+    release_channel_collection: opt-out
+    record_in_processes:
+      - main
 
 # The following section contains WebRTC nICEr scalars
 # For more info on ICE, see https://tools.ietf.org/html/rfc5245