Make DRT smarter about charset encoding when post-processing webarchive content

[David Kilzer (:ddkilzer)]

* SUMMARY
When attempting to create a layout test for Bug 22466, I tried moving fast/encoding/preload-encoding.html to an http test.  After setting the charset encoding for the "gb2312" files using a .htaccess file, I found that DRT would crash in convertWebResourceDataToString() because dataAsString was nil using the hard-coded UTF-8 encoding:

NSString *dataAsString = [[[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding] autorelease];
[resource setObject:dataAsString forKey:@"WebResourceData"];

* THE FIX
The better way to do this is to:

1. Attempt to convert the IANA charset into an NSStringEncoding value.
2. Check that dataAsString is non-nil before replacing it in the dictionary.

Instead of crashing, the worst that will happen is that the string data won't be decoded in the webarchive test output.

[David Kilzer (:ddkilzer)]

Created attachment 25488 [details]
Patch v1

Suggested fix.

No layout test since this is a DRT fix.

[David Kilzer (:ddkilzer)]

$ git svn dcommit
Committing to http://svn.webkit.org/repository/webkit/trunk ...
	M	WebKitTools/ChangeLog
	M	WebKitTools/DumpRenderTree/mac/DumpRenderTree.mm
Committed r38786

http://trac.webkit.org/changeset/38786