Use RetainPtr::autorelease in some places where it seems appropriate
https://bugs.webkit.org/show_bug.cgi?id=136280

Reviewed by Darin Adler.

Source/JavaScriptCore:

* API/JSContext.mm:
(-[JSContext name]): Use RetainPtr::autorelease() in place of ObjC autorelease.
* API/JSValue.mm:
(valueToString): Make appropriate use of RetainPtr

Source/WebCore:

* platform/mac/URLMac.mm:
(WebCore::URL::operator NSURL *): Use autorelease() instead of
CFBridgingRelease(leakRef())

Source/WebKit/mac:

* WebView/WebHTMLView.mm:
(imageFromRect): Use RetainPtr in this function.
* WebView/WebPDFRepresentation.mm:
(-[WebPDFRepresentation convertPostScriptDataSourceToPDF:]): Use RetainPtr
in this method.

Source/WebKit2:

* Shared/Cocoa/WKNSURLExtras.mm:
(urlWithWTFString): Use autorelease() instead of CFBridgingRelease(leakRef())

Source/WTF:

* wtf/text/mac/StringImplMac.mm:
(WTF::StringImpl::operator NSString *): Use autorelease() instead of
CFBridgingRelease(leakRef())


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@173141 268f45cc-cd09-0410-ab3c-d52691b4dbfc