Run clang-modernize -use-nullptr over src/extensions/.

extensions/common/manifest_handlers/file_handler_manifest_unittest.cc

 // Copyright 2014 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 "extensions/common/manifest_constants.h"
 #include "extensions/common/manifest_handlers/file_handler_info.h"
 #include "extensions/common/manifest_test.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace extensions {
@@ skipping 22 matching lines @@
   RunTestcases(testcases, arraysize(testcases), EXPECT_TYPE_ERROR);
 }
 
 TEST_F(FileHandlersManifestTest, ValidFileHandlers) {
   scoped_refptr<const Extension> extension =
       LoadAndExpectSuccess("file_handlers_valid.json");
 
   ASSERT_TRUE(extension.get());
   const FileHandlersInfo* handlers =
       FileHandlers::GetFileHandlers(extension.get());
-  ASSERT_TRUE(handlers != NULL);
+  ASSERT_TRUE(handlers != nullptr);
   ASSERT_EQ(2U, handlers->size());
 
   FileHandlerInfo handler = handlers->at(0);
   EXPECT_EQ("image", handler.id);
   EXPECT_EQ(1U, handler.types.size());
   EXPECT_EQ(1U, handler.types.count("image/*"));
   EXPECT_EQ(2U, handler.extensions.size());
   EXPECT_EQ(1U, handler.extensions.count(".png"));
   EXPECT_EQ(1U, handler.extensions.count(".gif"));
 
   handler = handlers->at(1);
   EXPECT_EQ("text", handler.id);
   EXPECT_EQ(1U, handler.types.size());
   EXPECT_EQ(1U, handler.types.count("text/*"));
   EXPECT_EQ(0U, handler.extensions.size());
 }
 
 TEST_F(FileHandlersManifestTest, NotPlatformApp) {
   // This should load successfully but have the file handlers ignored.
   scoped_refptr<const Extension> extension =
       LoadAndExpectSuccess("file_handlers_invalid_not_app.json");
 
   ASSERT_TRUE(extension.get());
   const FileHandlersInfo* handlers =
       FileHandlers::GetFileHandlers(extension.get());
-  ASSERT_TRUE(handlers == NULL);
+  ASSERT_TRUE(handlers == nullptr);
 }
 
 }  // namespace extensions