[Android]: Hide add-to-homescreen app menu item when WebAPK is installed

chrome/android/java/src/org/chromium/chrome/browser/metrics/WebApkUma.java

Index: chrome/android/java/src/org/chromium/chrome/browser/metrics/WebApkUma.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/metrics/WebApkUma.java b/chrome/android/java/src/org/chromium/chrome/browser/metrics/WebApkUma.java
index 87cb3db0ace0c30634d943f5cc5d1561357c5f4a..ef772ee7b72b23d459fc311fa6b8f403171f6587 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/metrics/WebApkUma.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/metrics/WebApkUma.java
@@ -4,6 +4,8 @@
 
 package org.chromium.chrome.browser.metrics;
 
+import android.support.annotation.IntDef;
+
 import org.chromium.base.metrics.RecordHistogram;
 
 /**
@@ -29,6 +31,15 @@ public class WebApkUma {
 
     public static final String HISTOGRAM_UPDATE_REQUEST_QUEUED = "WebApk.Update.RequestQueued";
 
+    // This enum is used to back UMA histograms, and should therefore be treated as append-only.
+    @IntDef({WEBAPK_OPEN_LAUNCH_SUCCESS, WEBAPK_OPEN_NO_LAUNCH_INTENT,
+            WEBAPK_OPEN_ACTIVITY_NOT_FOUND})
+    public @interface WebApkOpenResult {}
+    public static final int WEBAPK_OPEN_LAUNCH_SUCCESS = 0;
+    public static final int WEBAPK_OPEN_NO_LAUNCH_INTENT = 1;
+    public static final int WEBAPK_OPEN_ACTIVITY_NOT_FOUND = 2;
+    public static final int WEBAPK_OPEN_MAX = 3;
+
     /**
      * Records the time point when a request to update a WebAPK is sent to the WebAPK Server.
      * @param type representing when the update request is sent to the WebAPK server.
@@ -48,4 +59,14 @@ public class WebApkUma {
         RecordHistogram.recordEnumeratedHistogram(HISTOGRAM_UPDATE_REQUEST_QUEUED, times,
                 UPDATE_REQUEST_QUEUED_MAX);
     }
+
+    /**
+     * When a user presses on the "Open WebAPK" menu item, this records whether the WebAPK was
+     * opened successfully.
+     * @param type Result of trying to open WebAPK.
+     */
+    public static void recordWebApkOpenAttempt(@WebApkOpenResult int type) {
+        assert type >= 0 && type < WEBAPK_OPEN_MAX;
+        RecordHistogram.recordEnumeratedHistogram("WebApk.OpenFromMenu", type, WEBAPK_OPEN_MAX);
+    }
 }