Facts for pwa add to homescreen and install

Add facts to pwa docs

remove homescreen tap in favor of install

Author: Elise Richards

components/feature/pwa/README.md

@@ -65,6 +65,7 @@ This component emits the following [Facts](../../support/base/README.md#Facts):
 
 | Action | Item    | Extras         | Description                        |
 |--------|---------|----------------|------------------------------------|
+| CLICK  | install_shortcut  |   | The user installs a PWA shortcut. |
 | CLICK  | homescreen_icon_tap  |   | The user tapped the PWA icon on the homescreen. |
 | INTERACTION | enter_background | `itemExtras` | The current system time when the app is backgrounded. |
 | INTERACTION | enter_foreground | `itemExtras` | The current system time when the app is foregrounded. |

components/feature/pwa/src/main/java/mozilla/components/feature/pwa/ProgressiveWebAppFacts.kt

@@ -18,6 +18,7 @@ class ProgressiveWebAppFacts {
      * Items that specify which portion of the [PwaFeature] was interacted with
      */
     object Items {
+        const val INSTALL_SHORTCUT = "install_shortcut"
         const val HOMESCREEN_ICON_TAP = "homescreen_icon_tap"
         const val ENTER_BACKGROUND = "enter_background"
         const val ENTER_FOREGROUND = "enter_foreground"
@@ -58,6 +59,12 @@ internal fun emitHomescreenIconTapFact() =
         ProgressiveWebAppFacts.Items.HOMESCREEN_ICON_TAP
     )
 
+internal fun emitPwaInstallFact() =
+    emitPwaFact(
+        Action.CLICK,
+        ProgressiveWebAppFacts.Items.INSTALL_SHORTCUT
+    )
+
 internal fun emitForegroundTimingFact(timingNs: Long) =
     emitPwaFact(
         Action.INTERACTION,

components/feature/pwa/src/main/java/mozilla/components/feature/pwa/WebAppShortcutManager.kt

@@ -80,6 +80,7 @@ class WebAppShortcutManager(
         if (ShortcutManagerCompat.isRequestPinShortcutSupported(context)) {
             val manifest = session.installableManifest()
             val shortcut = if (supportWebApps && manifest != null) {
+                emitPwaInstallFact()
                 buildWebAppShortcut(context, manifest)
             } else {
                 buildBasicShortcut(context, session, overrideShortcutName)