Make content::ThrottlingURLLoader take a task runner and more efficient.

content/common/throttling_url_loader.cc

Index: content/common/throttling_url_loader.cc
diff --git a/content/common/throttling_url_loader.cc b/content/common/throttling_url_loader.cc
index 9f258c9d088eb45119684147f6e08bda2be1f69f..df1ef23f613f25ea9e3af6c98662d86d5944502a 100644
--- a/content/common/throttling_url_loader.cc
+++ b/content/common/throttling_url_loader.cc
@@ -4,8 +4,50 @@
 
 #include "content/common/throttling_url_loader.h"
 
+#include "base/single_thread_task_runner.h"
+
 namespace content {
 
+ThrottlingURLLoader::StartInfo::StartInfo(
+    mojom::URLLoaderFactory* in_url_loader_factory,
+    int32_t in_routing_id,
+    int32_t in_request_id,
+    uint32_t in_options,
+    std::unique_ptr<ResourceRequest> in_url_request,
+    scoped_refptr<base::SingleThreadTaskRunner> in_task_runner)
+    : url_loader_factory(in_url_loader_factory),
+      routing_id(in_routing_id),
+      request_id(in_request_id),
+      options(in_options),
+      url_request(std::move(in_url_request)),
+      task_runner(std::move(in_task_runner)) {}
+
+ThrottlingURLLoader::StartInfo::~StartInfo() = default;
+
+ThrottlingURLLoader::ResponseInfo::ResponseInfo(
+    const ResourceResponseHead& in_response_head,
+    const base::Optional<net::SSLInfo>& in_ssl_info,
+    mojom::DownloadedTempFilePtr in_downloaded_file)
+    : response_head(in_response_head),
+      ssl_info(in_ssl_info),
+      downloaded_file(std::move(in_downloaded_file)) {}
+
+ThrottlingURLLoader::ResponseInfo::~ResponseInfo() = default;
+
+ThrottlingURLLoader::RedirectInfo::RedirectInfo(
+    const net::RedirectInfo& in_redirect_info,
+    const ResourceResponseHead& in_response_head)
+    : redirect_info(in_redirect_info), response_head(in_response_head) {}
+
+ThrottlingURLLoader::RedirectInfo::~RedirectInfo() = default;
+
+ThrottlingURLLoader::PriorityInfo::PriorityInfo(
+    net::RequestPriority in_priority,
+    int32_t in_intra_priority_value)
+    : priority(in_priority), intra_priority_value(in_intra_priority_value) {}
+
+ThrottlingURLLoader::PriorityInfo::~PriorityInfo() = default;
+
 // static
 std::unique_ptr<ThrottlingURLLoader> ThrottlingURLLoader::CreateLoaderAndStart(
     mojom::URLLoaderFactory* factory,
@@ -14,11 +56,12 @@ std::unique_ptr<ThrottlingURLLoader> ThrottlingURLLoader::CreateLoaderAndStart(
     int32_t request_id,
     uint32_t options,
     std::unique_ptr<ResourceRequest> url_request,
-    mojom::URLLoaderClient* client) {
+    mojom::URLLoaderClient* client,
+    scoped_refptr<base::SingleThreadTaskRunner> task_runner) {
   std::unique_ptr<ThrottlingURLLoader> loader(
       new ThrottlingURLLoader(std::move(throttles), client));
   loader->Start(factory, routing_id, request_id, options,
-                std::move(url_request));
+                std::move(url_request), std::move(task_runner));
   return loader;
 }
 
@@ -33,9 +76,8 @@ void ThrottlingURLLoader::SetPriority(net::RequestPriority priority,
                                       int32_t intra_priority_value) {
   if (!url_loader_ && !cancelled_by_throttle_) {
     DCHECK_EQ(DEFERRED_START, deferred_stage_);
-    set_priority_cached_ = true;
-    priority_ = priority;
-    intra_priority_value_ = intra_priority_value;
+    priority_info_ =
+        base::MakeUnique<PriorityInfo>(priority, intra_priority_value);
     return;
   }
 
@@ -55,11 +97,13 @@ ThrottlingURLLoader::ThrottlingURLLoader(
   }
 }
 
-void ThrottlingURLLoader::Start(mojom::URLLoaderFactory* factory,
-                                int32_t routing_id,
-                                int32_t request_id,
-                                uint32_t options,
-                                std::unique_ptr<ResourceRequest> url_request) {
+void ThrottlingURLLoader::Start(
+    mojom::URLLoaderFactory* factory,
+    int32_t routing_id,
+    int32_t request_id,
+    uint32_t options,
+    std::unique_ptr<ResourceRequest> url_request,
+    scoped_refptr<base::SingleThreadTaskRunner> task_runner) {
   DCHECK_EQ(DEFERRED_NONE, deferred_stage_);
   DCHECK(!cancelled_by_throttle_);
 
@@ -72,18 +116,17 @@ void ThrottlingURLLoader::Start(mojom::URLLoaderFactory* factory,
 
     if (deferred) {
       deferred_stage_ = DEFERRED_START;
-      url_loader_factory_ = factory;
-      routing_id_ = routing_id;
-      request_id_ = request_id;
-      options_ = options;
-      url_request_ = std::move(url_request);
+      start_info_ = base::MakeUnique<StartInfo>(factory, routing_id, request_id,
+                                                options, std::move(url_request),
+                                                std::move(task_runner));
       return;
     }
   }
 
-  factory->CreateLoaderAndStart(mojo::MakeRequest(&url_loader_), routing_id,
-                                request_id, options, *url_request,
-                                client_binding_.CreateInterfacePtrAndBind());
+  factory->CreateLoaderAndStart(
+      mojo::MakeRequest(&url_loader_), routing_id, request_id, options,
+      *url_request,
+      client_binding_.CreateInterfacePtrAndBind(std::move(task_runner)));
 }
 
 void ThrottlingURLLoader::OnReceiveResponse(
@@ -101,9 +144,8 @@ void ThrottlingURLLoader::OnReceiveResponse(
 
     if (deferred) {
       deferred_stage_ = DEFERRED_RESPONSE;
-      response_head_ = response_head;
-      ssl_info_ = ssl_info;
-      downloaded_file_ = std::move(downloaded_file);
+      response_info_ = base::MakeUnique<ResponseInfo>(
+          response_head, ssl_info, std::move(downloaded_file));
       client_binding_.PauseIncomingMethodCallProcessing();
       return;
     }
@@ -127,8 +169,8 @@ void ThrottlingURLLoader::OnReceiveRedirect(
 
     if (deferred) {
       deferred_stage_ = DEFERRED_REDIRECT;
-      redirect_info_ = redirect_info;
-      response_head_ = response_head;
+      redirect_info_ =
+          base::MakeUnique<RedirectInfo>(redirect_info, response_head);
       client_binding_.PauseIncomingMethodCallProcessing();
       return;
     }
@@ -212,25 +254,31 @@ void ThrottlingURLLoader::Resume() {
 
   switch (deferred_stage_) {
     case DEFERRED_START: {
-      url_loader_factory_->CreateLoaderAndStart(
-          mojo::MakeRequest(&url_loader_), routing_id_, request_id_, options_,
-          *url_request_, client_binding_.CreateInterfacePtrAndBind());
-
-      if (set_priority_cached_) {
-        set_priority_cached_ = false;
-        url_loader_->SetPriority(priority_, intra_priority_value_);
+      start_info_->url_loader_factory->CreateLoaderAndStart(
+          mojo::MakeRequest(&url_loader_), start_info_->routing_id,
+          start_info_->request_id, start_info_->options,
+          *start_info_->url_request,
+          client_binding_.CreateInterfacePtrAndBind(
+              std::move(start_info_->task_runner)));
+
+      if (priority_info_) {
+        auto priority_info = std::move(priority_info_);
+        url_loader_->SetPriority(priority_info->priority,
+                                 priority_info->intra_priority_value);
       }
       break;
     }
     case DEFERRED_REDIRECT: {
       client_binding_.ResumeIncomingMethodCallProcessing();
-      forwarding_client_->OnReceiveRedirect(redirect_info_, response_head_);
+      forwarding_client_->OnReceiveRedirect(redirect_info_->redirect_info,
+                                            redirect_info_->response_head);
       break;
     }
     case DEFERRED_RESPONSE: {
       client_binding_.ResumeIncomingMethodCallProcessing();
-      forwarding_client_->OnReceiveResponse(response_head_, ssl_info_,
-                                            std::move(downloaded_file_));
+      forwarding_client_->OnReceiveResponse(
+          response_info_->response_head, response_info_->ssl_info,
+          std::move(response_info_->downloaded_file));
       break;
     }
     default: