Create libffmpeg.so in the component build.

Create libffmpeg.so in the component build.
Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=98577

[Ami GONE FROM CHROMIUM, 2011-08-28 00:40:23]

(sorry about previous empty email)
LGTM modulo not really knowing what this stuff does.  Hopefully you can trybot
the hell out of this change, or else wait for scherkus to review.

[darin (slow to review), 2011-08-28 04:07:35]

Thanks, but sadly there is no try bot coverage for this.  The linux_shared bot
does nothing more than test compilation.  I ran tests locally, and things look
good.

[darin (slow to review), 2011-08-28 04:09:05]

Also, let me explain this change a bit further:

I need to disable the visibility hidden compile time flag for this library so
that all of the non-static symbols it defines get exported.  This avoids the
need to tag each of the function declarations in the ffmpeg headers with a
compiler attribute to declare default visibility.

[scherkus (not reviewing), 2011-08-29 16:07:35]

On 2011/08/28 04:09:05, darin wrote:
> Also, let me explain this change a bit further:
> 
> I need to disable the visibility hidden compile time flag for this library so
> that all of the non-static symbols it defines get exported.  This avoids the
> need to tag each of the function declarations in the ffmpeg headers with a
> compiler attribute to declare default visibility.

post-commit LGTM!