[Cleanup] Remove useless code in service_worker_fetch_request.typemap

BUG=

Change-Id: I4ef96d8055825be72ac40bff03932a376bb018f4
Reviewed-on: https://chromium-review.googlesource.com/1187830Reviewed-by: Kinuko Yasuda <kinuko@chromium.org>
Commit-Queue: Han Leon <leon.han@intel.com>
Cr-Commit-Position: refs/heads/master@{#585721}

content/common/service_worker/service_worker_fetch_request.typemap

@@ -7,8 +7,6 @@ mojom =
 public_headers = [
   "//content/common/service_worker/service_worker_types.h",
   "//content/public/common/request_context_type.h",
-  "//storage/common/blob_storage/blob_handle.h",
-  "//storage/common/storage_common_export.h",
 ]
 traits_headers = [
   "//content/common/service_worker/service_worker_fetch_request_mojom_traits.h",
@@ -19,5 +17,4 @@ sources = [
 type_mappings = [
   "blink.mojom.FetchAPIRequest=::content::ServiceWorkerFetchRequest",
   "blink.mojom.RequestContextType=::content::RequestContextType",
-  "blink.mojom.ServiceWorkerFetchType=::content::ServiceWorkerFetchType",
 ]