Update references to Blink's Platform API headers

chrome/renderer/spellchecker/spellcheck_provider_mac_unittest.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 <vector>
 
 #include "base/utf_string_conversions.h"
 #include "chrome/common/spellcheck_messages.h"
 #include "chrome/common/spellcheck_result.h"
 #include "chrome/renderer/spellchecker/spellcheck_provider_test.h"
 #include "testing/gtest/include/gtest/gtest.h"
-#include "third_party/WebKit/Source/Platform/chromium/public/WebString.h"
+#include "third_party/WebKit/public/platform/WebString.h"
 
 namespace {
 
 class SpellCheckProviderMacTest : public SpellCheckProviderTest {};
 
 struct MessageParameters {
   MessageParameters()
       : router_id(0),
         request_id(0) {}
 
@@ skipping 68 matching lines @@
   EXPECT_EQ(completion2.completion_count_, 0U);
   EXPECT_EQ(provider_.pending_text_request_size(), 1U);
 
   FakeMessageArrival(&provider_, read_parameters2);
   EXPECT_EQ(completion1.completion_count_, 1U);
   EXPECT_EQ(completion2.completion_count_, 1U);
   EXPECT_EQ(provider_.pending_text_request_size(), 0U);
 }
 
 }  // namespace