Bug 1851820 - Send an event when Learn More is clicked r=aminomancer

Differential Revision: https://phabricator.services.mozilla.com/D187564

browser/components/newtab/aboutwelcome/lib/AboutWelcomeTelemetry.jsm

@@ -272,6 +272,10 @@ class AboutWelcomeTelemetry {
               // corresponds to "Not Now"
               Glean.shopping.surfaceNotNowClicked.record();
               break;
+            case "cta_paragraph":
+              // corresponds to "Learn More"
+              Glean.shopping.surfaceLearnMoreClicked.record();
+              break;
           }
           break;
         case "IMPRESSION":

browser/components/shopping/metrics.yaml

@@ -316,3 +316,22 @@ shopping:
       - fx-desktop-shopping-eng@mozilla.com
     send_in_pings:
       - events
+
+  surface_learn_more_clicked:
+    type: event
+    description: |
+      The user clicked the 'Learn More' link in the Shopping onboarding
+      experience.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1851820 
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1851820#c2
+    data_sensitivity:
+      - interaction
+    expires: 122
+    notification_emails:
+      - betling@mozilla.com
+      - fx-desktop-shopping-eng@mozilla.com
+    send_in_pings:
+      - events
+

browser/components/shopping/tests/browser/browser_shopping_onboarding.js

@@ -337,6 +337,35 @@ async function legalParagraphClickLinks() {
     }
   );
   await handleActionStubCalled;
+
+  handleActionStub.resetHistory();
+
+  handleActionStubCalled = new Promise(resolve =>
+    handleActionStub.callsFake(resolve)
+  );
+
+  await BrowserTestUtils.withNewTab(
+    {
+      url: "about:shoppingsidebar",
+      gBrowser,
+    },
+    async browser => {
+      await SpecialPowers.spawn(browser, [], async () => {
+        await ContentTaskUtils.waitForMutationCondition(
+          content.document,
+          { childList: true, subtree: true },
+          () => content.document.querySelector(".cta-paragraph a")
+        );
+        let cta = content.document.querySelector(
+          "shopping-container .cta-paragraph a"
+        );
+        // Learn More link button.
+        cta.click();
+      });
+    }
+  );
+  await handleActionStubCalled;
+
   sandbox.restore();
 }
 
@@ -367,6 +396,12 @@ add_task(async function test_linkParagraph() {
   Assert.greater(tosEvents.length, 0);
   Assert.equal(tosEvents[0].category, "shopping");
   Assert.equal(tosEvents[0].name, "surface_show_terms_clicked");
+
+  let learnMoreEvents = Glean.shopping.surfaceLearnMoreClicked.testGetValue();
+
+  Assert.greater(learnMoreEvents.length, 0);
+  Assert.equal(learnMoreEvents[0].category, "shopping");
+  Assert.equal(learnMoreEvents[0].name, "surface_learn_more_clicked");
 });
 
 add_task(async function test_onboarding_auto_activate_opt_in() {