Fix testSetPreviewTextureBothCallbacks wait timeout

The test assumes that
is the first callback to be called and
is called after. If onPreviewFrame is called first the CameraGLTest
will stop the camera preview which may cause onFrameAvailable to not
be called anymore.

Instead of stopping the camera preview in the onPreviewFrame function
the change stops the preview after each timeout wait in each test.

Change-Id: I18748fdca7a557ac059e69cfbfbcbf03e53bed49
1 file changed