stream: remove Array.p.shift primordial from hotpath of RS.read()

Refs: nodejs/performance#82

Author: debadree25

lib/internal/webstreams/readablestream.js

@@ -2084,7 +2084,7 @@ function readableStreamFulfillReadRequest(stream, chunk, done) {
     reader,
   } = stream[kState];
   assert(reader[kState].readRequests.length);
-  const readRequest = ArrayPrototypeShift(reader[kState].readRequests);
+  const readRequest = reader[kState].readRequests.shift();
 
   // TODO(@jasnell): It's not clear under what exact conditions done
   // will be true here. The spec requires this check but none of the
@@ -2102,7 +2102,7 @@ function readableStreamFulfillReadIntoRequest(stream, chunk, done) {
     reader,
   } = stream[kState];
   assert(reader[kState].readIntoRequests.length);
-  const readIntoRequest = ArrayPrototypeShift(reader[kState].readIntoRequests);
+  const readIntoRequest = reader[kState].readIntoRequests.shift();
   if (done)
     readIntoRequest[kClose](chunk);
   else