Merge EmbeddedTestServer#createAndStartDefaultServer() and createAndStartFileServer()

chrome/android/javatests/src/org/chromium/chrome/browser/PrerenderTest.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;
 
 import static org.chromium.base.test.util.Restriction.RESTRICTION_TYPE_NON_LOW_END_DEVICE;
 
-import android.os.Environment;
 import android.test.MoreAsserts;
 import android.test.suitebuilder.annotation.LargeTest;
 
 import org.chromium.base.ThreadUtils;
 import org.chromium.base.test.util.DisabledTest;
 import org.chromium.base.test.util.Feature;
 import org.chromium.base.test.util.FlakyTest;
 import org.chromium.base.test.util.Restriction;
 import org.chromium.base.test.util.RetryOnFailure;
 import org.chromium.chrome.browser.prerender.ExternalPrerenderHandler;
@@ skipping 11 matching lines @@
  *
  * Tests are disabled on low-end devices. These only support one renderer for performance reasons.
  */
 public class PrerenderTest extends ChromeTabbedActivityTestBase {
 
     private EmbeddedTestServer mTestServer;
 
     @Override
     protected void setUp() throws Exception {
         super.setUp();
-        mTestServer = EmbeddedTestServer.createAndStartFileServer(
-                getInstrumentation().getContext(), Environment.getExternalStorageDirectory());
+        mTestServer = EmbeddedTestServer.createAndStartServer(getInstrumentation().getContext());
     }
 
     @Override
     protected void tearDown() throws Exception {
         mTestServer.stopAndDestroyServer();
         super.tearDown();
     }
 
     /**
      * We are using Autocomplete Action Predictor to decide whether or not to prerender.
@@ skipping 91 matching lines @@
                 handler.cancelCurrentPrerender();
             }
         });
     }
 
     @Override
     public void startMainActivity() throws InterruptedException {
         startMainActivityOnBlankPage();
     }
 }