Valgrind: Fix a leak in GetValueFromDictionary for cocoa.

Valgrind: Fix a leak in GetValueFromDictionary for cocoa.

BUG=none
TEST=none

R=mark@chromium.org

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=110359

[Mark Mentovai, 2011-11-16 19:08:31]

Thank you. LGTM.

[Mark Mentovai, 2011-11-16 19:09:04]

+kushi.p as FYI.

[KushalP, 2011-11-16 19:56:40]

On 2011/11/16 19:09:04, Mark Mentovai wrote:
> +kushi.p as FYI.

Can you clear something up for me please: is this because no CFRelease had been
called on the value provided by CFCopyTypeIDDescription?

If so, could this also be done by assigning it to a value like so:

  CFStringRef expected_type_name = CFCopyTypeIDDescription(expected_type);

and then after the DLOG on line 245, calling CFRelease(expected_type_name).

I realise it's bad code when ScopedCFTypeRef exists, but does it achieve the
same thing?

[Mark Mentovai, 2011-11-16 20:00:51]

That’s correct. We use ScopedCFTypeRef<> to ensure that the object gets released
even if someone comes along in the future and adds an early return. It’s also
generally cleaner to not have to maintain gross return-path code. If we were
using C++ exceptions (we’re not), ScopedCFTypeRef<> would be the only way to
ensure that the object was released.