Verify intent signatures.

chrome/android/java/src/org/chromium/chrome/browser/externalnav/ExternalNavigationDelegateImpl.java

 // Copyright 2015 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.chrome.browser.externalnav;
 
 import android.Manifest.permission;
 import android.app.Activity;
 import android.content.Context;
 import android.content.DialogInterface;
@@ skipping 524 matching lines @@
         if (TextUtils.isEmpty(fileExtension)) return false;
 
         return PDF_EXTENSION.equals(fileExtension);
     }
 
     @Override
     public void maybeRecordAppHandlersInIntent(Intent intent, List<ResolveInfo> infos) {
         intent.putExtra(IntentHandler.EXTRA_EXTERNAL_NAV_PACKAGES,
                 getSpecializedHandlersWithFilter(infos, null));
     }
+
+    @Override
+    public Context getAssociatedActivityContext() {
+        return mApplicationContext;
+    }
 }