Move usage of QualityScaler to ViEEncoder.

webrtc/video_encoder.h

Index: webrtc/video_encoder.h
diff --git a/webrtc/video_encoder.h b/webrtc/video_encoder.h
index 3a997176a980b6aafc9fda79dfe8de89c84cb7f3..c749a82261aef60c6f42dbc40f667b46b526186d 100644
--- a/webrtc/video_encoder.h
+++ b/webrtc/video_encoder.h
@@ -19,6 +19,7 @@
 #include "webrtc/common_types.h"
 #include "webrtc/typedefs.h"
 #include "webrtc/video_frame.h"
+#include "webrtc/base/optional.h"
 
 namespace webrtc {
 
@@ -69,7 +70,20 @@ class VideoEncoder {
     kVp9,
     kUnsupportedCodec,
   };
-
+  struct QpThresholds {
+    QpThresholds(int l, int h) : low(l), high(h) {}
+    QpThresholds() : low(-1), high(-1) {}
+    int low;
+    int high;
+  };
+  struct ScalingSettings {
+    ScalingSettings(bool on, int low, int high)
+        : enabled(on),
+          thresholds(rtc::Optional<QpThresholds>(QpThresholds(low, high))) {}
+    explicit ScalingSettings(bool on) : enabled(on) {}
+    const bool enabled;
+    const rtc::Optional<QpThresholds> thresholds;
+  };
   static VideoEncoder* Create(EncoderType codec_type);
   // Returns true if this type of encoder can be created using
   // VideoEncoder::Create.
@@ -161,6 +175,12 @@ class VideoEncoder {
     return SetRates(allocation.get_sum_kbps(), framerate);
   }
 
+  // Any encoder implementation wishing to use the WebRTC provided
+  // quality scaler must implement this method.
+  virtual ScalingSettings GetScalingSettings() const {
+    return ScalingSettings(false);
+  }
+
   virtual int32_t SetPeriodicKeyFrames(bool enable) { return -1; }
   virtual void OnDroppedFrame() {}
   virtual bool SupportsNativeHandle() const { return false; }