Refactor parameter passing to decoders and split backend/decode-only and frontend renderers

app/streaming/video/ffmpeg-renderers/vaapi.h

@@ -30,12 +30,7 @@ class VAAPIRenderer : public IFFmpegRenderer
 public:
     VAAPIRenderer();
     virtual ~VAAPIRenderer();
-    virtual bool initialize(SDL_Window* window,
-                            int videoFormat,
-                            int width,
-                            int height,
-                            int maxFps,
-                            bool enableVsync);
+    virtual bool initialize(PDECODER_PARAMETERS params);
     virtual bool prepareDecoderContext(AVCodecContext* context);
     virtual void renderFrame(AVFrame* frame);
     virtual bool needsTestFrame();