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

chrome/android/webapk/libs/client/src/org/chromium/webapk/lib/client/WebApkValidator.java

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 package org.chromium.webapk.lib.client;
 
 import static org.chromium.webapk.lib.common.WebApkConstants.WEBAPK_PACKAGE_PREFIX;
 
 import android.content.Context;
 import android.content.Intent;
@@ skipping 22 matching lines @@
      * handler is the WebAPK.
      *
      * NOTE(yfriedman): This can fail if multiple WebAPKs can match the supplied url.
      *
      * @param context The application context.
      * @param url The url to check.
      * @return Package name of WebAPK which can handle the URL. Null if the url should not be
      * handled by a WebAPK.
      */
     public static String queryWebApkPackage(Context context, String url) {
+        List<ResolveInfo> resolveInfos = resolveInfosForUrl(context, url);
+        if (resolveInfos == null) {
+            return null;
+        }
+        return findWebApkPackage(context, resolveInfos);
+    }
+
+    /**
+     * Queries the PackageManager to determine whether a WebAPK can handle the URL. Ignores
+     * whether the user has selected a default handler for the URL and whether the default
+     * handler is the WebAPK.
+     *
+     * NOTE: This can fail if multiple WebAPKs can match the supplied url.
+     *
+     * @param context The application context.
+     * @param url The url to check.
+     * @return Resolve Info of a WebAPK which can handle the URL. Null if the url should not be
+     * handled by a WebAPK.
+     */
+    public static ResolveInfo queryWebApk(Context context, String url) {
+        List<ResolveInfo> resolveInfos = resolveInfosForUrl(context, url);
+        if (resolveInfos == null) {
+            return null;
+        }
+
+        for (ResolveInfo info : resolveInfos) {
+            if (info.activityInfo != null
+                    && isValidWebApk(context, info.activityInfo.packageName)) {
+                return info;
+            }
+        }
+        return null;
+    }
+
+    /**
+     * Fetches the list of resolve infos from the PackageManager that can handle the URL.
+     *
+     * @param context The application context.
+     * @param url The url to check.
+     * @return The list of resolve infos found that can handle the URL.
+     */
+    private static List<ResolveInfo> resolveInfosForUrl(Context context, String url) {

[dominickn, 2017/02/21 23:04:42]

It would be nice if this method never returned null, and gave back an empty list
when an exception happened. That way you can remove a bunch of null checks
because they'll just work (iteration over an empty list).

E.g. PackageManager#queryIntentActivities returns an empty list when it doesn't
find anything.

[gonzalon, 2017/02/22 15:50:49]

Done.

         Intent intent;
         try {
             intent = Intent.parseUri(url, Intent.URI_INTENT_SCHEME);
         } catch (Exception e) {
             return null;
         }
 
         intent.addCategory(Intent.CATEGORY_BROWSABLE);
         intent.setComponent(null);
         Intent selector = intent.getSelector();
         if (selector != null) {
             selector.addCategory(Intent.CATEGORY_BROWSABLE);
             selector.setComponent(null);
         }
-
-        List<ResolveInfo> resolveInfos = context.getPackageManager().queryIntentActivities(
+        return context.getPackageManager().queryIntentActivities(
                 intent, PackageManager.GET_RESOLVED_FILTER);
-        return findWebApkPackage(context, resolveInfos);
     }
 
     /**
      * @param context The context to use to check whether WebAPK is valid.
      * @param infos The ResolveInfos to search.
      * @return Package name of the ResolveInfo which corresponds to a WebAPK. Null if none of the
      * ResolveInfos corresponds to a WebAPK.
      */
     public static String findWebApkPackage(Context context, List<ResolveInfo> infos) {
         for (ResolveInfo info : infos) {
@@ skipping 48 matching lines @@
      * with for the current host.
      * @param expectedSignature
      */
     public static void initWithBrowserHostSignature(byte[] expectedSignature) {
         if (sExpectedSignature != null) {
             return;
         }
         sExpectedSignature = Arrays.copyOf(expectedSignature, expectedSignature.length);
     }
 }