Make nesting/running states a RunLoop rather than a MessageLoop concept.

third_party/WebKit/Source/platform/scheduler/base/task_queue_manager_unittest.cc

Index: third_party/WebKit/Source/platform/scheduler/base/task_queue_manager_unittest.cc
diff --git a/third_party/WebKit/Source/platform/scheduler/base/task_queue_manager_unittest.cc b/third_party/WebKit/Source/platform/scheduler/base/task_queue_manager_unittest.cc
index 8befec1209593698d3eca668836756947c11d581..37e58574fa318099cad17f175bd576b07963946f 100644
--- a/third_party/WebKit/Source/platform/scheduler/base/task_queue_manager_unittest.cc
+++ b/third_party/WebKit/Source/platform/scheduler/base/task_queue_manager_unittest.cc
@@ -66,19 +66,19 @@ class MessageLoopTaskRunner : public TaskQueueManagerDelegateForTest {
     return make_scoped_refptr(new MessageLoopTaskRunner(std::move(tick_clock)));
   }
 
-  // NestableTaskRunner implementation.
+  // TaskQueueManagerDelegateForTest:
   bool IsNested() const override {
-    return base::MessageLoop::current()->IsNested();
+    DCHECK(RunsTasksOnCurrentThread());
+    return base::RunLoop::IsNestedOnCurrentThread();
   }
 
-  void AddNestingObserver(
-      base::MessageLoop::NestingObserver* observer) override {
-    base::MessageLoop::current()->AddNestingObserver(observer);
+  void AddNestingObserver(base::RunLoop::NestingObserver* observer) override {
+    base::RunLoop::AddNestingObserverOnCurrentThread(observer);
   }
 
   void RemoveNestingObserver(
-      base::MessageLoop::NestingObserver* observer) override {
-    base::MessageLoop::current()->RemoveNestingObserver(observer);
+      base::RunLoop::NestingObserver* observer) override {
+    base::RunLoop::RemoveNestingObserverOnCurrentThread(observer);
   }
 
  private:
@@ -1262,7 +1262,7 @@ TEST_F(TaskQueueManagerTest, DelayedTaskDoesNotSkipAHeadOfShorterDelayedTask) {
 }
 
 void CheckIsNested(bool* is_nested) {
-  *is_nested = base::MessageLoop::current()->IsNested();
+  *is_nested = base::RunLoop::IsNestedOnCurrentThread();
 }
 
 void PostAndQuitFromNestedRunloop(base::RunLoop* run_loop,