Getting ecm files from the ECM package

[Stephen Kelly]

Sune Vuorela wrote:

> On 2013-11-03, Alexander Neundorf <neundorf at kde.org> wrote:
>> This code unconditionally searches for QtCore (and sets a target property
>> where I'm not sure how many people here can understand what's going on).
> 
> It is hopefully a temporary hack that shouldn't be in that file.

Yes. 

> Sometimes, temporary hacks in development stuff is unfortunately needed,
> but I do hope that whoever introduced it has a plan to get it out.

It has been very common throughout the development of KF5 so far. 

FindQt5Transitional had all kinds of hacks to account for Qt not yet having 
particular features yet, and CMake not having particular features yet. Now 
FindQt5Transitional is not used at all because our version requirements are 
such that it is not needed. It's a natural lifecycle of hacks. 

This particular hack under discussion is another case of exactly the same 
thing.

> I agree that finding ECM should just be finding ECM and not requiring a
> Qt install.

Plan A: Don't release ECM until CMake 3.0 is out.
Plan B: Remove the hack when releasing KArchive and threadweaver. Accept any 
possible fallout.

Thanks,

Steve.