Fix silent truncations when extracting values from CheckedNumeric

chrome/browser/chromeos/file_system_provider/fileapi/file_stream_reader_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 "chrome/browser/chromeos/file_system_provider/fileapi/file_stream_reader.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <memory>
@@ skipping 114 matching lines @@
   storage::FileSystemURL wrong_file_url_;
 };
 
 TEST_F(FileSystemProviderFileStreamReader, Read_AllAtOnce) {
   EventLogger logger;
 
   const int64_t initial_offset = 0;
   FileStreamReader reader(NULL, file_url_, initial_offset,
                           *fake_file_->metadata->modification_time);
   scoped_refptr<net::IOBuffer> io_buffer(new net::IOBuffer(
-      base::CheckedNumeric<size_t>(*fake_file_->metadata->size).ValueOrDie()));
+      base::checked_cast<size_t>(*fake_file_->metadata->size)));
 
   const int result =
       reader.Read(io_buffer.get(), *fake_file_->metadata->size,
                   base::Bind(&EventLogger::OnRead, logger.GetWeakPtr()));
   EXPECT_EQ(net::ERR_IO_PENDING, result);
   base::RunLoop().RunUntilIdle();
 
   ASSERT_EQ(1u, logger.results().size());
   EXPECT_LT(0, logger.results()[0]);
   EXPECT_EQ(*fake_file_->metadata->size, logger.results()[0]);
 
   std::string buffer_as_string(io_buffer->data(), *fake_file_->metadata->size);
   EXPECT_EQ(fake_file_->contents, buffer_as_string);
 }
 
 TEST_F(FileSystemProviderFileStreamReader, Read_WrongFile) {
   EventLogger logger;
 
   const int64_t initial_offset = 0;
   FileStreamReader reader(NULL, wrong_file_url_, initial_offset,
                           *fake_file_->metadata->modification_time);
   scoped_refptr<net::IOBuffer> io_buffer(new net::IOBuffer(
-      base::CheckedNumeric<size_t>(*fake_file_->metadata->size).ValueOrDie()));
+      base::checked_cast<size_t>(*fake_file_->metadata->size)));
 
   const int result =
       reader.Read(io_buffer.get(), *fake_file_->metadata->size,
                   base::Bind(&EventLogger::OnRead, logger.GetWeakPtr()));
   EXPECT_EQ(net::ERR_IO_PENDING, result);
   base::RunLoop().RunUntilIdle();
 
   ASSERT_EQ(1u, logger.results().size());
   EXPECT_EQ(net::ERR_FILE_NOT_FOUND, logger.results()[0]);
 }
@@ skipping 74 matching lines @@
   EXPECT_EQ(fake_file_->contents, buffer_as_string);
 }
 
 TEST_F(FileSystemProviderFileStreamReader, Read_ModifiedFile) {
   EventLogger logger;
 
   const int64_t initial_offset = 0;
   FileStreamReader reader(NULL, file_url_, initial_offset, base::Time::Max());
 
   scoped_refptr<net::IOBuffer> io_buffer(new net::IOBuffer(
-      base::CheckedNumeric<size_t>(*fake_file_->metadata->size).ValueOrDie()));
+      base::checked_cast<size_t>(*fake_file_->metadata->size)));
   const int result =
       reader.Read(io_buffer.get(), *fake_file_->metadata->size,
                   base::Bind(&EventLogger::OnRead, logger.GetWeakPtr()));
 
   EXPECT_EQ(net::ERR_IO_PENDING, result);
   base::RunLoop().RunUntilIdle();
 
   ASSERT_EQ(1u, logger.results().size());
   EXPECT_EQ(net::ERR_UPLOAD_FILE_CHANGED, logger.results()[0]);
 }
 
 TEST_F(FileSystemProviderFileStreamReader, Read_ExpectedModificationTimeNull) {
   EventLogger logger;
 
   const int64_t initial_offset = 0;
   FileStreamReader reader(NULL, file_url_, initial_offset, base::Time());
 
   scoped_refptr<net::IOBuffer> io_buffer(new net::IOBuffer(
-      base::CheckedNumeric<size_t>(*fake_file_->metadata->size).ValueOrDie()));
+      base::checked_cast<size_t>(*fake_file_->metadata->size)));
   const int result =
       reader.Read(io_buffer.get(), *fake_file_->metadata->size,
                   base::Bind(&EventLogger::OnRead, logger.GetWeakPtr()));
 
   EXPECT_EQ(net::ERR_IO_PENDING, result);
   base::RunLoop().RunUntilIdle();
 
   ASSERT_EQ(1u, logger.results().size());
   EXPECT_EQ(*fake_file_->metadata->size, logger.results()[0]);
 
@@ skipping 61 matching lines @@
   EXPECT_EQ(net::ERR_IO_PENDING, result);
   base::RunLoop().RunUntilIdle();
 
   ASSERT_EQ(1u, logger.results().size());
   EXPECT_LT(0, logger.results()[0]);
   EXPECT_EQ(*fake_file_->metadata->size, logger.results()[0]);
 }
 
 }  // namespace file_system_provider
 }  // namespace chromeos