Add a chrome://webapks page.

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

Index: chrome/android/webapk/libs/client/src/org/chromium/webapk/lib/client/WebApkValidator.java
diff --git a/chrome/android/webapk/libs/client/src/org/chromium/webapk/lib/client/WebApkValidator.java b/chrome/android/webapk/libs/client/src/org/chromium/webapk/lib/client/WebApkValidator.java
index 377494bdae5659ecf521421ede980fe4317abced..bb1e2ec37140302172b5b7efc06dda697d881154 100644
--- a/chrome/android/webapk/libs/client/src/org/chromium/webapk/lib/client/WebApkValidator.java
+++ b/chrome/android/webapk/libs/client/src/org/chromium/webapk/lib/client/WebApkValidator.java
@@ -69,7 +69,6 @@ public class WebApkValidator {
     public static String findWebApkPackage(Context context, List<ResolveInfo> infos) {
         for (ResolveInfo info : infos) {
             if (info.activityInfo != null
-                    && info.activityInfo.packageName.startsWith(WEBAPK_PACKAGE_PREFIX)
                     && isValidWebApk(context, info.activityInfo.packageName)) {
                 return info.activityInfo.packageName;
             }
@@ -83,11 +82,14 @@ public class WebApkValidator {
      * @param webappPackageName The package name to check
      * @return true iff the WebAPK is installed and passes security checks
      */
-    private static boolean isValidWebApk(Context context, String webappPackageName) {
+    public static boolean isValidWebApk(Context context, String webappPackageName) {
         if (sExpectedSignature == null) {
             Log.wtf(TAG, "WebApk validation failure - expected signature not set."
                     + "missing call to WebApkValidator.initWithBrowserHostSignature");
         }
+        if (!webappPackageName.startsWith(WEBAPK_PACKAGE_PREFIX)) {
+            return false;
+        }
         // check signature
         PackageInfo packageInfo = null;
         try {