[net] Subtract timestamps to determine if uploading file changed.

net/base/upload_file_element_reader_unittest.cc

Index: net/base/upload_file_element_reader_unittest.cc
diff --git a/net/base/upload_file_element_reader_unittest.cc b/net/base/upload_file_element_reader_unittest.cc
index b0374acd966ba694ea832f5bba57bc116fff5195..bf896a1420a443847dc4ce258e6520afe6da9f90 100644
--- a/net/base/upload_file_element_reader_unittest.cc
+++ b/net/base/upload_file_element_reader_unittest.cc
@@ -221,6 +221,20 @@ TEST_F(UploadFileElementReaderTest, FileChanged) {
   EXPECT_EQ(ERR_UPLOAD_FILE_CHANGED, init_callback.WaitForResult());
 }
 
+TEST_F(UploadFileElementReaderTest, InexactExpectedTimeStamp) {
+  base::File::Info info;
+  ASSERT_TRUE(base::GetFileInfo(temp_file_path_, &info));
+
+  const base::Time expected_modification_time =
+      info.last_modified - base::TimeDelta::FromMilliseconds(900);
+  reader_.reset(new UploadFileElementReader(
+      base::MessageLoopProxy::current().get(), temp_file_path_, 0, kuint64max,
+      expected_modification_time));

[mmenke, 2015/02/02 15:34:21]

nit:  While you're here, should format the identical line in the above and below
tests to match this one, to make it clearer the tests are doing the exact same
thing here.

+  TestCompletionCallback init_callback;
+  ASSERT_EQ(ERR_IO_PENDING, reader_->Init(init_callback.callback()));
+  EXPECT_EQ(OK, init_callback.WaitForResult());
+}
+
 TEST_F(UploadFileElementReaderTest, WrongPath) {
   const base::FilePath wrong_path(FILE_PATH_LITERAL("wrong_path"));
   reader_.reset(