Apply idle optimizations throughout code base

Summary:
See explanation in parent diff, make sure the idler is used efficiently, instead of wasting a lot of CPU creating a new callstack every time `idle` is called.

Also fixed that cancelled idlers could result in an _uncaught_ exception

Reviewed By: nikoant

Differential Revision: D19158593

fbshipit-source-id: 0be505a74c374e0ca6ee0e79b1f1e98ac9b80467

src/utils/serialization.tsx

@@ -136,7 +136,7 @@ export async function makeObjectSerializable(
   let prevStackLength = stack.length;
   let accumulator = prevStackLength;
   while (stack.length > 0) {
-    if (idler) {
+    if (idler && idler.shouldIdle()) {
       await idler.idle();
     }
     const element = stack[stack.length - 1];