Use LoadingTaskRunner for cancel_timer_ of Resource class

third_party/WebKit/Source/platform/loader/fetch/Resource.cpp

Index: third_party/WebKit/Source/platform/loader/fetch/Resource.cpp
diff --git a/third_party/WebKit/Source/platform/loader/fetch/Resource.cpp b/third_party/WebKit/Source/platform/loader/fetch/Resource.cpp
index c874c0774d0fe3f576d001693dc6f832285fbfa3..10a3a9caab3da052047ddc6975f434d98bc9974f 100644
--- a/third_party/WebKit/Source/platform/loader/fetch/Resource.cpp
+++ b/third_party/WebKit/Source/platform/loader/fetch/Resource.cpp
@@ -269,12 +269,14 @@ Resource::Resource(const ResourceRequest& request,
       integrity_disposition_(ResourceIntegrityDisposition::kNotChecked),
       options_(options),
       response_timestamp_(CurrentTime()),
-      cancel_timer_(IsMainThread()
-                        ? Platform::Current()->MainThread()->GetWebTaskRunner()
-                        : Platform::Current()
-                              ->CurrentThread()
-                              ->Scheduler()
-                              ->LoadingTaskRunner(),
+      cancel_timer_(IsMainThread() ? Platform::Current()

[kinuko, 2017/05/15 06:24:48]

Can you add a short comment like: 'we use MainThread() for main-thread cases to
avoid TLS cost to retrieve the current thread'

[horo, 2017/05/15 06:38:41]

Done.

+                                         ->MainThread()
+                                         ->Scheduler()
+                                         ->LoadingTaskRunner()
+                                   : Platform::Current()
+                                         ->CurrentThread()
+                                         ->Scheduler()
+                                         ->LoadingTaskRunner(),
                     this,
                     &Resource::CancelTimerFired),
       resource_request_(request) {