I started (https://codereview.chromium.org/812403002/) emulating oflag values
on Windows in FileWriter, but it seemed awkward. On the assumption that we're
only likely to need "read a file" and "write a file" this seemed simpler, and
sufficient (but I don't know if that's necessarily true).
Users of open are not yet switched.
R=mark@chromium.org
BUG=crashpad:1
Review URL: https://codereview.chromium.org/818433002
Rename fd_io to file_io, and ReadFD to ReadFile, etc.
file_io.cc is the higher level versions that call the basic ReadFile/WriteFile
and then file_io_posix.cc and file_io_win.cc are the implementations of
those functions.
The Windows path is as yet untested, lacking the ability to link the test binary.
R=cpu@chromium.org, mark@chromium.org
BUG=crashpad:1
Review URL: https://codereview.chromium.org/811823003
