Remove FileProtocolHandler on iOS.

Internal requests should not end up in file URLs, and Safari handles
other requests, so we shouldn't need it. FileProtocoloHandler is no
longer in use on other platforms, so we should be able to delete it.

Bug: 934009
Change-Id: I00749a080b8bcda2a3ff4655a40ce9835e42e608
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1783911Reviewed-by: Eugene But <eugenebut@chromium.org>
Commit-Queue: Matt Menke <mmenke@chromium.org>
Cr-Commit-Position: refs/heads/master@{#693787}

ios/chrome/browser/browser_state/chrome_browser_state_io_data.h

@@ -67,10 +67,6 @@ class ChromeBrowserStateIOData {
 
   virtual ~ChromeBrowserStateIOData();
 
-  // Returns true if |scheme| is handled in Chrome, or by default handlers in
-  // net::URLRequest.
-  static bool IsHandledProtocol(const std::string& scheme);
-
   // Utility to install additional WebUI handlers into the |job_factory|.
   // Ownership of the handlers is transferred from |protocol_handlers|
   // to the |job_factory|.

ios/chrome/browser/browser_state/chrome_browser_state_io_data.mm

@@ -58,7 +58,6 @@
 #include "net/proxy_resolution/proxy_resolution_service.h"
 #include "net/traffic_annotation/network_traffic_annotation.h"
 #include "net/url_request/data_protocol_handler.h"
-#include "net/url_request/file_protocol_handler.h"
 #include "net/url_request/report_sender.h"
 #include "net/url_request/url_request.h"
 #include "net/url_request/url_request_context.h"
@@ -218,19 +217,6 @@ ChromeBrowserStateIOData::~ChromeBrowserStateIOData() {
   }
 }
 
-// static
-bool ChromeBrowserStateIOData::IsHandledProtocol(const std::string& scheme) {
-  DCHECK_EQ(scheme, base::ToLowerASCII(scheme));
-  static const char* const kProtocolList[] = {
-      url::kFileScheme, kChromeUIScheme, url::kDataScheme, url::kAboutScheme,
-  };
-  for (size_t i = 0; i < base::size(kProtocolList); ++i) {
-    if (scheme == kProtocolList[i])
-      return true;
-  }
-  return net::URLRequest::IsHandledProtocol(scheme);
-}
-
 // static
 void ChromeBrowserStateIOData::InstallProtocolHandlers(
     net::URLRequestJobFactoryImpl* job_factory,
@@ -415,17 +401,7 @@ std::unique_ptr<net::URLRequestJobFactory>
 ChromeBrowserStateIOData::SetUpJobFactoryDefaults(
     std::unique_ptr<net::URLRequestJobFactoryImpl> job_factory,
     net::NetworkDelegate* network_delegate) const {
-  // NOTE(willchan): Keep these protocol handlers in sync with
-  // ChromeBrowserStateIOData::IsHandledProtocol().
   bool set_protocol = job_factory->SetProtocolHandler(
-      url::kFileScheme,
-      std::make_unique<net::FileProtocolHandler>(base::CreateTaskRunner(
-          {base::ThreadPool(), base::MayBlock(),
-           base::TaskPriority::BEST_EFFORT,
-           base::TaskShutdownBehavior::SKIP_ON_SHUTDOWN})));
-  DCHECK(set_protocol);
-
-  set_protocol = job_factory->SetProtocolHandler(
       url::kDataScheme, std::make_unique<net::DataProtocolHandler>());
   DCHECK(set_protocol);