remove implementation of obsolete WebKitPlatformSupport::prefetchHostName.

webkit/support/test_webkit_platform_support.cc

 // Copyright (c) 2012 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.
 
 #include "webkit/support/test_webkit_platform_support.h"
 
 #include "base/command_line.h"
 #include "base/file_util.h"
 #include "base/files/scoped_temp_dir.h"
 #include "base/metrics/stats_counters.h"
@@ skipping 174 matching lines @@
 
 bool TestWebKitPlatformSupport::isLinkVisited(unsigned long long linkHash) {
   return false;
 }
 
 WebKit::WebMessagePortChannel*
 TestWebKitPlatformSupport::createMessagePortChannel() {
   return new TestWebMessagePortChannel();
 }
 
-void TestWebKitPlatformSupport::prefetchHostName(const WebKit::WebString&) {
-}
-
 WebKit::WebURLLoader* TestWebKitPlatformSupport::createURLLoader() {
   return url_loader_factory_.CreateURLLoader(
       webkit_glue::WebKitPlatformSupportImpl::createURLLoader());
 }
 
 WebKit::WebData TestWebKitPlatformSupport::loadResource(const char* name) {
   if (!strcmp(name, "deleteButton")) {
     // Create a red 30x30 square.
     const char red_square[] =
         "\x89\x50\x4e\x47\x0d\x0a\x1a\x0a\x00\x00\x00\x0d\x49\x48\x44\x52"
@@ skipping 237 matching lines @@
   return view.release();
 }
 
 WebKit::WebLayerTreeView*
     TestWebKitPlatformSupport::createLayerTreeViewForTesting(
         TestViewType type) {
   DCHECK_EQ(TestViewTypeUnitTest, type);
   return createLayerTreeViewForTesting();
 }