Convert pdfium to use LF instead of CRLF for EOL

Convert pdfium to use LF instead of CRLF for EOL

Normalize the whole repository to use "LF" instead of "CRLF" for line endings.

Add a .gitattributes with "* text=auto" so that new lines are
automatically converted to the native platform's format on checkout but
are committed as "LF".

BUG=375516

[jln (very slow on Chromium), 2014-05-23 23:28:46]

This does two things:
1. Convert the repository to consistently use LF instead of CRLF (there were
only a few offending files).
2. Add a .gitattributes file to force the correct behavior.

Let me know if you would rather have me submit two CLs.

The documentation is surprisingly confusing, but I think this is the right thing
to do.
It should be similar to what SVN does.

[jam, 2014-05-24 00:19:47]

lgtm, thanks!

[jam, 2014-05-24 00:33:14]

btw so i ran 

find . -type f -exec dos2unix {} \;

and I found that most files had Windows line endings. i'm not sure why it shows
that for me but not for you. how did you check?

I couldn't patch your cl since git cl patch seems to have problems patching
files with windows line endings, so i'll copy your .gitattribute file manually.

[jam, 2014-05-24 00:48:40]

Landed in
https://pdfium.googlesource.com/pdfium/+/5b51e49beb646a378f5cbaf012ff63c98234...

[jln (very slow on Chromium), 2014-05-27 20:35:41]

On 2014/05/24 00:33:14, jam wrote:
> btw so i ran 
> 
> find . -type f -exec dos2unix {} \;
> 
> and I found that most files had Windows line endings. i'm not sure why it
shows
> that for me but not for you. how did you check?

Yeah, I suspect the review tool skipped them for when I uploaded. I'm not sure
why this would have happened.