[InstalledApp] Limit the number of related apps used.

Only take the first 3 related apps declared in the web manifest into
account when determining if there are any related apps.

Change-Id: I4a0ba7372351f3b4e541a920794aaaab812184f9
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1953715
Commit-Queue: Rayan Kanso <rayankans@chromium.org>
Reviewed-by: Peter Beverloo <peter@chromium.org>
Cr-Commit-Position: refs/heads/master@{#722532}

chrome/android/java/src/org/chromium/chrome/browser/installedapp/InstalledAppProviderImpl.java

@@ -50,6 +50,11 @@ public class InstalledAppProviderImpl implements InstalledAppProvider {
     @VisibleForTesting
     public static final String INSTANT_APP_HOLDBACK_ID_STRING = "instantapp:holdback";
 
+    // The maximum number of related apps declared in the Web Manifest taken into account when
+    // determining whether the related app is installed and mutually related.
+    @VisibleForTesting
+    static final int MAX_ALLOWED_RELATED_APPS = 3;
+
     private static final String TAG = "InstalledAppProvider";
 
     private final FrameUrlDelegate mFrameUrlDelegate;
@@ -85,7 +90,6 @@ public class InstalledAppProviderImpl implements InstalledAppProvider {
     public void filterInstalledApps(
             final RelatedApplication[] relatedApps, final FilterInstalledAppsResponse callback) {
         final URI frameUrl = mFrameUrlDelegate.getUrl();
-
         // Use an AsyncTask to execute the installed/related checks on a background thread (so as
         // not to block the UI thread).
         new AsyncTask<Pair<RelatedApplication[], Integer>>() {
@@ -133,7 +137,8 @@ public class InstalledAppProviderImpl implements InstalledAppProvider {
         ArrayList<RelatedApplication> installedApps = new ArrayList<RelatedApplication>();
         int delayMillis = 0;
         PackageManager pm = mContext.getPackageManager();
-        for (RelatedApplication app : relatedApps) {
+        for (int i = 0; i < Math.min(relatedApps.length, MAX_ALLOWED_RELATED_APPS); i++) {
+            RelatedApplication app = relatedApps[i];
             // If the package is of type "play", it is installed, and the origin is associated with
             // package, add the package to the list of valid packages.
             // NOTE: For security, it must not be possible to distinguish (from the response)

chrome/android/junit/src/org/chromium/chrome/browser/installedapp/InstalledAppProviderTest.java

@@ -47,6 +47,8 @@ public class InstalledAppProviderTest {
             InstalledAppProviderImpl.ASSET_STATEMENT_NAMESPACE_WEB;
     private static final String PLATFORM_ANDROID =
             InstalledAppProviderImpl.RELATED_APP_PLATFORM_ANDROID;
+    private static final int MAX_ALLOWED_RELATED_APPS =
+            InstalledAppProviderImpl.MAX_ALLOWED_RELATED_APPS;
     private static final String PLATFORM_OTHER = "itunes";
     // Note: Android package name and origin deliberately unrelated (there is no requirement that
     // they be the same).
@@ -785,14 +787,13 @@ public class InstalledAppProviderTest {
         RelatedApplication[] manifestRelatedApps = new RelatedApplication[] {
                 createRelatedApplication(PLATFORM_ANDROID, PACKAGE_NAME_1, null),
                 createRelatedApplication(PLATFORM_ANDROID, PACKAGE_NAME_2, null),
-                createRelatedApplication(PLATFORM_OTHER, PACKAGE_NAME_2, null),
                 createRelatedApplication(PLATFORM_ANDROID, PACKAGE_NAME_3, null)};
 
         setAssetStatement(PACKAGE_NAME_2, NAMESPACE_WEB, RELATION_HANDLE_ALL_URLS, ORIGIN);
         setAssetStatement(PACKAGE_NAME_3, NAMESPACE_WEB, RELATION_HANDLE_ALL_URLS, ORIGIN);
 
         RelatedApplication[] expectedInstalledRelatedApps =
-                new RelatedApplication[] {manifestRelatedApps[1], manifestRelatedApps[3]};
+                new RelatedApplication[] {manifestRelatedApps[1], manifestRelatedApps[2]};
         verifyInstalledApps(manifestRelatedApps, expectedInstalledRelatedApps);
     }
 
@@ -829,10 +830,6 @@ public class InstalledAppProviderTest {
     public void testMultipleAppsIncludingInstantApps() {
         RelatedApplication[] manifestRelatedApps = new RelatedApplication[] {
                 createRelatedApplication(PLATFORM_ANDROID, PACKAGE_NAME_1, null),
-                createRelatedApplication(PLATFORM_ANDROID, PACKAGE_NAME_2, null),
-                createRelatedApplication(PLATFORM_OTHER, PACKAGE_NAME_2, null),
-                createRelatedApplication(PLATFORM_ANDROID, PACKAGE_NAME_3, null),
-
                 // Instant Apps:
                 createRelatedApplication(
                         PLATFORM_ANDROID, InstalledAppProviderImpl.INSTANT_APP_ID_STRING, ORIGIN),
@@ -843,7 +840,30 @@ public class InstalledAppProviderTest {
         mFakeInstantAppsHandler.addInstantApp(ORIGIN, true);
 
         RelatedApplication[] expectedInstalledRelatedApps =
-                new RelatedApplication[] {manifestRelatedApps[0], manifestRelatedApps[5]};
+                new RelatedApplication[] {manifestRelatedApps[0], manifestRelatedApps[2]};
+        verifyInstalledApps(manifestRelatedApps, expectedInstalledRelatedApps);
+    }
+
+    /**
+     * Multiple related uninstalled apps (over the allowed limit) followed by one related Android
+     * app which is installed and mutually related.
+     */
+    @Test
+    @Feature({"InstalledApp"})
+    public void testRelatedAppsOverAllowedThreshold() {
+        RelatedApplication manifestRelatedApps[] =
+                new RelatedApplication[MAX_ALLOWED_RELATED_APPS + 1];
+        for (int i = 0; i < MAX_ALLOWED_RELATED_APPS; i++) {
+            manifestRelatedApps[i] = createRelatedApplication(
+                    PLATFORM_ANDROID, PACKAGE_NAME_2 + String.valueOf(i), null);
+        }
+        manifestRelatedApps[MAX_ALLOWED_RELATED_APPS] =
+                createRelatedApplication(PLATFORM_ANDROID, PACKAGE_NAME_1, null);
+        setAssetStatement(PACKAGE_NAME_1, NAMESPACE_WEB, RELATION_HANDLE_ALL_URLS, ORIGIN);
+
+        // Although the app is installed, and verifiable, it was included after the maximum allowed
+        // number of related apps.
+        RelatedApplication[] expectedInstalledRelatedApps = new RelatedApplication[] {};
         verifyInstalledApps(manifestRelatedApps, expectedInstalledRelatedApps);
     }
 }