More efficient reading of java.time.Duration values using Scala.js

Author: plokhotnyuk

jsoniter-scala-core/js/src/main/scala/com/github/plokhotnyuk/jsoniter_scala/core/JsonReader.scala

@@ -2917,7 +2917,7 @@ final class JsonReader private[jsoniter_scala](
         state = 0
       } else if (b == 'H' && state <= 0) {
         if (x < -2562047788015215L || x > 2562047788015215L) durationError(pos) // -2562047788015215L == Long.MinValue / 3600
-        seconds = sumSeconds(x * 3600, seconds, pos)
+        seconds = sumSeconds((x << 12) - (x << 9) + (x << 4), seconds, pos)
         state = 1
       } else if (b == 'M' && state <= 1) {
         if (x < -153722867280912930L || x > 153722867280912930L) durationError(pos) // -153722867280912930L == Long.MinValue / 60