Read contents of test file after getting its absolute path.

chrome/test/remoting/remote_desktop_browsertest.cc

Index: chrome/test/remoting/remote_desktop_browsertest.cc
diff --git a/chrome/test/remoting/remote_desktop_browsertest.cc b/chrome/test/remoting/remote_desktop_browsertest.cc
index b1d5717fcda55ac6b14875e7534da2038b612598..ec370d7be582df84539b2fdebe197de54a62fd12 100644
--- a/chrome/test/remoting/remote_desktop_browsertest.cc
+++ b/chrome/test/remoting/remote_desktop_browsertest.cc
@@ -826,14 +826,12 @@ void RemoteDesktopBrowserTest::SetUserNameAndPassword(
   // ReadFile instead.
   int64 accounts_file_size;
   base::GetFileSize(accounts_file_path, &accounts_file_size);
-  // There is a compile error on Windows if you use a non-constant array size.
-  // For the test-accounts file, we'll assume a maximum file size of 10K.
-  char buf[10240];
-  ASSERT_FALSE(base::ReadFile(accounts_file_path, buf, accounts_file_size - 1)
-    == -1);
+  scoped_ptr<char[]> file_contents(new char[accounts_file_size]);

[Jamie, 2014/10/25 00:05:14]

scoped_array feels like a better fit here:
https://code.google.com/p/chromium/codesearch#chromium/src/third_party/cld/ba...

[anandc, 2014/10/27 19:17:53]

As discussed offline, scoped_ptr does the work of delete[], so it should do for
our purposes.

+  ASSERT_FALSE(base::ReadFile(accounts_file_path, file_contents.get(),

[Lambros, 2014/10/25 00:13:09]

ASSERT_NE

[anandc, 2014/10/27 19:17:52]

Done.

+    accounts_file_size) == -1);
 
   // Get the root dictionary from the input json file contents.
-  std::string accounts_info(buf);
+  std::string accounts_info(file_contents.get(), accounts_file_size);

[Lambros, 2014/10/25 00:13:09]

Why not use base::ReadFileToString() ?

[anandc, 2014/10/27 19:17:53]

Yes, we actually were using ReadFileToString earlier. See comment on line #824
of this patch.
But ReadFileToString doesn't work when the path to the file is relative. 
See comment here:
https://code.google.com/p/chromium/codesearch#chromium/src/base/files/file_ut...
On the Chromoting waterfall, the input file path is going to be relative on the
test slaves. So we have to use Read() instead.

[Lambros, 2014/10/27 21:20:49]

Sorry, I didn't see the comment. Maybe call base::MakeAbsoluteFilePath() to
convert to an absolute path, and then pass that in to base::ReadFileToString() ?

Re-implementing ReadFileToString() from scratch to circumvent a security
limitation doesn't seem the right thing to do.

[anandc, 2014/10/27 22:18:57]

Done.

   scoped_ptr<base::Value> root(
       base::JSONReader::Read(accounts_info, base::JSON_ALLOW_TRAILING_COMMAS));