Revert of Revert "Post loading tasks on the appropriate WebFrameScheduler's queue."

content/child/resource_scheduling_filter.cc

Index: content/child/resource_scheduling_filter.cc
diff --git a/content/child/resource_scheduling_filter.cc b/content/child/resource_scheduling_filter.cc
index 843cd8713f4c58047c2a4699a9a88875d51e5acf..6445c00a2b55b2545944b177ae7d380930679c58 100644
--- a/content/child/resource_scheduling_filter.cc
+++ b/content/child/resource_scheduling_filter.cc
@@ -9,8 +9,31 @@
 #include "content/child/resource_dispatcher.h"
 #include "ipc/ipc_message.h"
 #include "ipc/ipc_message_start.h"
+#include "third_party/WebKit/public/platform/WebTaskRunner.h"
+#include "third_party/WebKit/public/platform/WebTraceLocation.h"
 
 namespace content {
+
+namespace {
+class DispatchMessageTask : public blink::WebTaskRunner::Task {
+ public:
+  DispatchMessageTask(
+      base::WeakPtr<ResourceSchedulingFilter> resource_scheduling_filter,
+      const IPC::Message& message)
+    : resource_scheduling_filter_(resource_scheduling_filter),
+      message_(message) {}
+
+  void run() override {
+    if (!resource_scheduling_filter_.get())
+      return;
+    resource_scheduling_filter_->DispatchMessage(message_);
+  }
+
+ private:
+  base::WeakPtr<ResourceSchedulingFilter> resource_scheduling_filter_;
+  const IPC::Message message_;
+};
+} // namespace
 
 ResourceSchedulingFilter::ResourceSchedulingFilter(
     const scoped_refptr<base::SingleThreadTaskRunner>& main_thread_task_runner,
@@ -26,10 +49,40 @@
 }
 
 bool ResourceSchedulingFilter::OnMessageReceived(const IPC::Message& message) {
-  main_thread_task_runner_->PostTask(
-      FROM_HERE, base::Bind(&ResourceSchedulingFilter::DispatchMessage,
-                            weak_ptr_factory_.GetWeakPtr(), message));
+  base::AutoLock lock(request_id_to_task_runner_map_lock_);
+  int request_id;
+
+  base::PickleIterator pickle_iterator(message);
+  if (!pickle_iterator.ReadInt(&request_id)) {
+    NOTREACHED() << "malformed resource message";
+    return true;
+  }
+  // Dispatch the message on the request id specific task runner, if there is
+  // one, or on the general main_thread_task_runner if there isn't.
+  RequestIdToTaskRunnerMap::const_iterator iter =
+      request_id_to_task_runner_map_.find(request_id);
+  if (iter != request_id_to_task_runner_map_.end()) {
+    // TODO(alexclarke): Find a way to let blink and chromium FROM_HERE coexist.
+    iter->second->postTask(
+        blink::WebTraceLocation(__FUNCTION__, __FILE__),
+        new DispatchMessageTask(weak_ptr_factory_.GetWeakPtr(), message));
+  } else {
+    main_thread_task_runner_->PostTask(
+        FROM_HERE, base::Bind(&ResourceSchedulingFilter::DispatchMessage,
+                              weak_ptr_factory_.GetWeakPtr(), message));
+  }
   return true;
+}
+
+void ResourceSchedulingFilter::SetRequestIdTaskRunner(
+    int id, scoped_ptr<blink::WebTaskRunner> web_task_runner) {
+  base::AutoLock lock(request_id_to_task_runner_map_lock_);
+  request_id_to_task_runner_map_.insert(id, web_task_runner.Pass());
+}
+
+void ResourceSchedulingFilter::ClearRequestIdTaskRunner(int id) {
+  base::AutoLock lock(request_id_to_task_runner_map_lock_);
+  request_id_to_task_runner_map_.erase(id);
 }
 
 bool ResourceSchedulingFilter::GetSupportedMessageClasses(