Fix build break for chrome os.

Fix build break for chrome os.

Add #include <stdio.h> for fclose et al.
Without stdio.h, we got errors like:
In file included from /usr/local/google/home/ukai/chrome/src/chrome/browser/chromeos/pipe_reader.cc:5:
/usr/local/google/home/ukai/chrome/src/chrome/browser/chromeos/pipe_reader.h: In destructor 'virtual PipeReader::~PipeReader()':
/usr/local/google/home/ukai/chrome/src/chrome/browser/chromeos/pipe_reader.h:33: error: 'fclose' was not declared in this scope
/usr/local/google/home/ukai/chrome/src/chrome/browser/chromeos/pipe_reader.cc: In member function 'virtual std::string PipeReader::Read(uint32)':
/usr/local/google/home/ukai/chrome/src/chrome/browser/chromeos/pipe_reader.cc:11: error: 'fopen' was not declared in this scope
/usr/local/google/home/ukai/chrome/src/chrome/browser/chromeos/pipe_reader.cc:12: error: 'fgets' was not declared in this scope
scons: *** [/usr/local/google/home/ukai/chrome/src/sconsbuild/Debug/obj/chrome/browser/chromeos/pipe_reader.o] Error 1

[Chris Masone, 2009-09-08 15:11:16]

Lgtm