docs: function(protoIRs) {
        protoIRs.forEach(function(apir) {
          // Only consider animations for now.
          if (apir.irType !== ProtoIR.ANIMATION_TYPE)
            return;
  
          protoIRs.forEach(function(rpir) {
            // Only consider responses for now.
            if (rpir.irType !== ProtoIR.RESPONSE_TYPE)
              return;
  
            // Only consider responses that end during the animation.
            if (!apir.containsTimestampInclusive(rpir.end))
              return;
  
            // Ignore Responses that are entirely contained by the animation.
            if (apir.containsTimestampInclusive(rpir.start))
              return;
  
            // Move the animation start to the response end.
            apir.start = rpir.end;
          });
        });
        return protoIRs;
      }