[Adaptation] Make QuailtyScalerResourse to report underuse if quality…

… scaling is off

Bug: chromium:1080789
Change-Id: I3aefb746fd6f4adae4b32db322af6b787e8ede1d
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/174804
Commit-Queue: Ilya Nikolaevskiy <ilnik@webrtc.org>
Commit-Queue: Henrik Boström <hbos@webrtc.org>
Reviewed-by: Henrik Boström <hbos@webrtc.org>
Reviewed-by: Evan Shrubsole <eshr@google.com>
Cr-Commit-Position: refs/heads/master@{#31213}

call/adaptation/resource_adaptation_processor_unittest.cc

@@ -325,4 +325,26 @@ TEST_F(ResourceAdaptationProcessorTest,
   EXPECT_FALSE(resource_.usage_state().has_value());
 }
 
+TEST_F(ResourceAdaptationProcessorTest,
+       AdaptsDownWhenOtherResourceIsAlwaysUnderused) {
+  processor_.SetDegradationPreference(
+      DegradationPreference::MAINTAIN_FRAMERATE);
+  processor_.StartResourceAdaptation();
+  SetInputStates(true, kDefaultFrameRate, kDefaultFrameSize);
+  other_resource_.set_usage_state(ResourceUsageState::kUnderuse);
+  // Does not trigger adapataion because there's no restriction.
+  EXPECT_EQ(0, processor_listener_.adaptation_counters().Total());
+
+  RestrictSource(processor_listener_.restrictions());
+  resource_.set_usage_state(ResourceUsageState::kOveruse);
+  // Adapts down even if other resource asked for adapting up.
+  EXPECT_EQ(1, processor_listener_.adaptation_counters().Total());
+
+  RestrictSource(processor_listener_.restrictions());
+  other_resource_.set_usage_state(ResourceUsageState::kUnderuse);
+  // Doesn't adapt up because adaptation is due to another resource.
+  EXPECT_EQ(1, processor_listener_.adaptation_counters().Total());
+  RestrictSource(processor_listener_.restrictions());
+}
+
 }  // namespace webrtc

video/adaptation/quality_scaler_resource.cc

@@ -50,8 +50,16 @@ bool QualityScalerResource::QpFastFilterLow() {
 
 void QualityScalerResource::OnEncodeCompleted(const EncodedImage& encoded_image,
                                               int64_t time_sent_in_us) {
-  if (quality_scaler_ && encoded_image.qp_ >= 0)
+  if (quality_scaler_ && encoded_image.qp_ >= 0) {
     quality_scaler_->ReportQp(encoded_image.qp_, time_sent_in_us);
+  } else if (!quality_scaler_) {
+    // TODO(webrtc:11553): this is a workaround to ensure that all quality
+    // scaler imposed limitations are removed once qualty scaler is disabled
+    // mid call.
+    // Instead it should be done at a higher layer in the same way for all
+    // resources.
+    OnResourceUsageStateMeasured(ResourceUsageState::kUnderuse);
+  }
 }
 
 void QualityScalerResource::OnFrameDropped(