Bug 1249094 - Add UI Telemetry probes for application foreground / background changes r=margaret

mobile/android/base/java/org/mozilla/gecko/TelemetryContract.java

@@ -188,6 +188,9 @@ public interface TelemetryContract {
         // Action triggered from a suggestion provided to the user.
         SUGGESTION("suggestion"),
 
+        // Action triggered from an OS system action.
+        SYSTEM("system"),
+
         // Action triggered from the Tabs tray.
         TABSTRAY("tabstray"),
 

mobile/android/chrome/content/browser.js

@@ -6801,6 +6801,8 @@ var ActivityObserver = {
     let isForeground = false;
     let tab = BrowserApp.selectedTab;
 
+    UITelemetry.addEvent("show.1", "system", null, aTopic);
+
     switch (aTopic) {
       case "application-background" :
         let doc = (tab ? tab.browser.contentDocument : null);
@@ -6828,7 +6830,6 @@ var Telemetry = {
 };
 
 var Experiments = {
-
   // Enable malware download protection (bug 936041)
   MALWARE_DOWNLOAD_PROTECTION: "malware-download-protection",
 

mobile/android/docs/uitelemetry.rst

@@ -230,6 +230,9 @@ Methods
 ``suggestion``
   Action triggered from a suggested result, like those from search engines or default tiles.
 
+``system``
+  Action triggered from an OS level action, like application foreground / background.
+
 ``toast``
   Action triggered from an unobtrusive, temporary notification.