Use TaskScheduler instead of blocking pool in content_hash_fetcher.cc.

extensions/browser/content_hash_fetcher.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "extensions/browser/content_hash_fetcher.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <memory>
 #include <vector>
 
 #include "base/base64.h"
 #include "base/files/file_enumerator.h"
 #include "base/files/file_util.h"
 #include "base/json/json_reader.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/metrics/histogram_macros.h"
 #include "base/synchronization/lock.h"
-#include "base/task_runner_util.h"
-#include "base/threading/sequenced_worker_pool.h"
+#include "base/task_scheduler/post_task.h"
 #include "base/timer/elapsed_timer.h"
 #include "base/version.h"
 #include "content/public/browser/browser_thread.h"
 #include "crypto/sha2.h"
 #include "extensions/browser/computed_hashes.h"
 #include "extensions/browser/content_hash_tree.h"
 #include "extensions/browser/content_verifier_delegate.h"
 #include "extensions/browser/verified_contents.h"
 #include "extensions/common/constants.h"
 #include "extensions/common/extension.h"
@@ skipping 156 matching lines @@
       block_size_(4096),
       cancelled_(false) {
   bool got_id =
       content::BrowserThread::GetCurrentThreadIdentifier(&creation_thread_);
   DCHECK(got_id);
 }
 
 void ContentHashFetcherJob::Start() {
   base::FilePath verified_contents_path =
       file_util::GetVerifiedContentsPath(extension_path_);
-  base::PostTaskAndReplyWithResult(
-      content::BrowserThread::GetBlockingPool(),
-      FROM_HERE,
-      base::Bind(&ContentHashFetcherJob::LoadVerifiedContents,
-                 this,
+  base::PostTaskWithTraitsAndReplyWithResult(
+      FROM_HERE, base::TaskTraits().MayBlock().WithPriority(
+                     base::TaskPriority::USER_VISIBLE),
+      base::Bind(&ContentHashFetcherJob::LoadVerifiedContents, this,
                  verified_contents_path),
       base::Bind(&ContentHashFetcherJob::DoneCheckingForVerifiedContents,
                  this));
 }
 
 void ContentHashFetcherJob::Cancel() {
   base::AutoLock autolock(cancelled_lock_);
   cancelled_ = true;
 }
 
@@ skipping 68 matching lines @@
   // the right cookies).  TODO(asargent) - It would be a nice enhancement to
   // move to parsing this in a sandboxed helper (crbug.com/372878).
   std::unique_ptr<base::Value> parsed(base::JSONReader::Read(*response));
   if (parsed) {
     VLOG(1) << "JSON parsed ok for " << extension_id_;
 
     parsed.reset();  // no longer needed
     base::FilePath destination =
         file_util::GetVerifiedContentsPath(extension_path_);
     size_t size = response->size();
-    base::PostTaskAndReplyWithResult(
-        content::BrowserThread::GetBlockingPool(),
-        FROM_HERE,
+    base::PostTaskWithTraitsAndReplyWithResult(
+        FROM_HERE, base::TaskTraits().MayBlock().WithPriority(
+                       base::TaskPriority::BACKGROUND),

[Devlin, 2017/02/16 16:59:42]

ditto:
USER_VISIBLE

This is in response to loading an extension, and may result in the extension
becoming disabled or notifying the user of corruption.

(Would have mentioned this in the previous patch set, but this wasn't changed in
PS2)

         base::Bind(&WriteFileHelper, destination, base::Passed(&response)),
-        base::Bind(
-            &ContentHashFetcherJob::OnVerifiedContentsWritten, this, size));
+        base::Bind(&ContentHashFetcherJob::OnVerifiedContentsWritten, this,
+                   size));
   } else {
     DoneFetchingVerifiedContents(false);
   }
 }
 
 void ContentHashFetcherJob::OnVerifiedContentsWritten(size_t expected_size,
                                                       int write_result) {
   bool success =
       (write_result >= 0 && static_cast<size_t>(write_result) == expected_size);
   DoneFetchingVerifiedContents(success);
@@ skipping 191 matching lines @@
 
   for (JobMap::iterator i = jobs_.begin(); i != jobs_.end(); ++i) {
     if (i->second.get() == job) {
       jobs_.erase(i);
       break;
     }
   }
 }
 
 }  // namespace extensions