Use TaskScheduler instead of WorkerPool in url_data_manager_backend.cc.

content/browser/webui/url_data_manager_backend.cc

Index: content/browser/webui/url_data_manager_backend.cc
diff --git a/content/browser/webui/url_data_manager_backend.cc b/content/browser/webui/url_data_manager_backend.cc
index 246a443c2b2442950e8eea3ba5f1dc1d9c73b9ca..47deeb80bb3a59a0522b1ca0a9d84b2af5c86906 100644
--- a/content/browser/webui/url_data_manager_backend.cc
+++ b/content/browser/webui/url_data_manager_backend.cc
@@ -23,8 +23,8 @@
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
+#include "base/task_scheduler/post_task.h"
 #include "base/threading/thread_task_runner_handle.h"
-#include "base/threading/worker_pool.h"
 #include "base/trace_event/trace_event.h"
 #include "content/browser/blob_storage/chrome_blob_storage_context.h"
 #include "content/browser/histogram_internals_request_job.h"
@@ -478,9 +478,11 @@ int URLRequestChromeJob::PostReadTask(scoped_refptr<net::IOBuffer> buf,
   if (buf_size == 0)
     return 0;
 
-  base::WorkerPool::GetTaskRunner(false)->PostTaskAndReply(
-      FROM_HERE, base::Bind(&CopyData, base::RetainedRef(buf), buf_size, data_,
-                            data_offset_),
+  base::PostTaskWithTraitsAndReply(
+      FROM_HERE, base::TaskTraits().WithShutdownBehavior(
+                     base::TaskShutdownBehavior::CONTINUE_ON_SHUTDOWN),

[Dan Beam, 2017/01/02 19:55:22]

i don't know how easy it is to do, but it'd be nice to up the priority on these
tasks when the tab in is the foreground.  as in: WithPriority(USER_BLOCKING)

[fdoray, 2017/01/02 19:58:28]

We have plan to add a context trait. There will be a context for each tab. It
will be possible to dynamically change the priority of all tasks for a given
context. I took a note to add the context trait to this task once we implement
it.

+      base::Bind(&CopyData, base::RetainedRef(buf), buf_size, data_,
+                 data_offset_),
       base::Bind(&URLRequestChromeJob::ReadRawDataComplete, AsWeakPtr(),
                  buf_size));
   data_offset_ += buf_size;