Tune QP threshold for HW codecs.

Lower down bad thresholds a bit to avoid staying
at 720p resolution at 300 - 500 kbps.

R=wzh@webrtc.org

Review URL: https://codereview.webrtc.org/1954433002 .

Cr-Commit-Position: refs/heads/master@{#12633}
diff --git a/webrtc/api/java/jni/androidmediaencoder_jni.cc b/webrtc/api/java/jni/androidmediaencoder_jni.cc
index b7f2da4..7a13270 100644
--- a/webrtc/api/java/jni/androidmediaencoder_jni.cc
+++ b/webrtc/api/java/jni/androidmediaencoder_jni.cc
@@ -392,15 +392,15 @@
       // always = 127. Note that in SW, QP is that of the user-level range [0,
       // 63].
       const int kLowQpThreshold = 29;
-      const int kBadQpThreshold = 100;
+      const int kBadQpThreshold = 90;
       quality_scaler_.Init(kLowQpThreshold, kBadQpThreshold,
                            codec_settings->startBitrate, codec_settings->width,
                            codec_settings->height,
                            codec_settings->maxFramerate);
     } else if (codecType_ == kVideoCodecH264) {
       // H264 QP is in the range [0, 51].
-      const int kLowQpThreshold = 24;
-      const int kBadQpThreshold = 39;
+      const int kLowQpThreshold = 22;
+      const int kBadQpThreshold = 35;
       quality_scaler_.Init(kLowQpThreshold, kBadQpThreshold,
                            codec_settings->startBitrate, codec_settings->width,
                            codec_settings->height,