Revert cloneDeep-ing request headers (#10215)

* Support cloning Symbols in cloneDeep

* Revert "Support cloning Symbols in cloneDeep"

This reverts commit 2d5f4b1.

* Revert "Ensure getResultsFromLink writes results using original options."

This reverts commit b4ffcb6

src/core/QueryManager.ts

@@ -26,7 +26,6 @@ import {
   makeUniqueId,
   isDocumentNode,
   isNonNullObject,
-  cloneDeep,
 } from '../utilities';
 import { ApolloError, isApolloError } from '../errors';
 import {
@@ -1038,10 +1037,6 @@ export class QueryManager<TStore> {
   ): Observable<ApolloQueryResult<TData>> {
     const requestId = queryInfo.lastRequestId = this.generateRequestId();
 
-    // Make sure we write the result below using the same options we were given,
-    // even though the input object may have been modified in the meantime.
-    options = cloneDeep(options);
-
     // Performing transformForLink here gives this.cache a chance to fill in
     // missing fragment definitions (for example) before sending this document
     // through the link chain.