Revert "glimagesink: need add glFinish after eglswapbuffer"

To quote the upstream maintainers:
"glFinish() after swapBuffers is a no-go performance wise [...]
The question is why do you need this in the first place ?"

glFinish stalls the entire GPU pipeline, which severely degrades
performance in pipelines with multiple branches, such as:

glupload ! tee name=t
  t. ! queue ! glfilter ! gldownload ! ...
  t. ! glimagesink

glFinish at the end in glimagesink halts until any and all work
in the pipeline context is done on the GPU including in the upper
branch although that isn't required. This makes both branches go
slower. It also doesn't fix any tearing issues as that's properly
handled by sync fences already.

This reverts commit 397e0e785fae2da048bf9bfc3e12f572e9a26bc7.

Change-Id: I6bdbe33fab36a976969e10d28e95190e47f50766
1 file changed