[PATCH] Avoid invalidating successfully loaded module files

[Argyrios Kyrtzidis]

LGTM.

> On Jun 19, 2014, at 4:15 PM, Ben Langmuir <blangmuir at apple.com> wrote:
> 
>    Avoid invalidating successfully loaded module files
> 
>    Successfully loaded module files may be referenced in other
>    ModuleManagers, so don't invalidate them. Two related things are fixed:
> 
>    1) I thought the last module in the manager was always the one that
>    failed, but it isn't.  So check explicitly against the list of
>    vetted modules from ReadASTCore.
> 
>    2) We now keep the file descriptor of pcm file open, which avoids the
>    possibility of having two different pcms for the same module loaded when
>    building in parallel with headers being modified during a build.
> 
> Ben
> <invalidate.patch>