[webkit-dev] Experimental features enabled at runtime

[Brady Eidson]

> On Nov 5, 2016, at 6:18 PM, Michael Catanzaro <mcatanzaro at igalia.com> wrote:
> 
> On Sat, 2016-11-05 at 16:03 -0700, Ryosuke Niwa wrote:
>> Maybe what we really need is one set of defaults that are appropriate
>>> for development (our bots, ENABLE(DEVELOPER_MODE), Safari Tech
>> Preview,
>>> etc.) and a different set of defaults that are appropriate for
>> stable
>>> releases and end users.
>> 
>> 
>> That makes sense.  Ideally,
>> FOR_EACH_WEBKIT_EXPERIMENTAL_FEATURE_PREFERENCE
>> is only used for features that need to be enabled in those "beta" or
>> "developer" versions of each port's browser.
> 
> Yeah, it could be as simple as all those experimental features are
> enabled by default in the ENABLE(DEVELOPER_MODE) case, and they're all
> disabled otherwise. Though then there's no way to have features
> runtime-enabled features that are too unstable even for Tech Preview.
> 
> All CMake ports support ENABLE(DEVELOPER_MODE); is that defined
> anywhere with the XCode build?

I still don't think this is right.

Safari might want to enable a "disabled by default" feature for a release, or it might want to disable an "enabled by default" feature for a release.

We'd do so by changing the default value in the code and then checking that in to our branch for that release.

In this same vein, "trunk" is a "branch" for a certain type of release (WebKit nightly, STP, etc) where I think there's arguments to be made on a per-feature basis that it be either disabled or enabled by default.

Thanks,
~Brady