Threading: Add thread checks in TaskRunnerHelper

third_party/WebKit/Source/core/dom/TaskRunnerHelper.cpp

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "core/dom/TaskRunnerHelper.h"
 
 #include "core/dom/Document.h"
 #include "core/dom/ExecutionContext.h"
 #include "core/frame/LocalFrame.h"
 #include "core/workers/WorkerOrWorkletGlobalScope.h"
 #include "core/workers/WorkerThread.h"
 #include "platform/WebFrameScheduler.h"
 #include "platform/WebTaskRunner.h"
 #include "public/platform/Platform.h"
 #include "public/platform/WebThread.h"
 
 namespace blink {
 
 RefPtr<WebTaskRunner> TaskRunnerHelper::Get(TaskType type, LocalFrame* frame) {
+  DCHECK(WTF::IsMainThread());
   // TODO(haraken): Optimize the mapping from TaskTypes to task runners.
   switch (type) {
     case TaskType::kTimer:
       return frame ? frame->FrameScheduler()->TimerTaskRunner()
                    : Platform::Current()->CurrentThread()->GetWebTaskRunner();
     case TaskType::kUnspecedLoading:
     case TaskType::kNetworking:
       return frame ? frame->FrameScheduler()->LoadingTaskRunner()
                    : Platform::Current()->CurrentThread()->GetWebTaskRunner();
     // Throttling following tasks may break existing web pages, so tentatively
@@ skipping 24 matching lines @@
     case TaskType::kMiscPlatformAPI:
     case TaskType::kUnthrottled:
       return frame ? frame->FrameScheduler()->UnthrottledTaskRunner()
                    : Platform::Current()->CurrentThread()->GetWebTaskRunner();
   }
   NOTREACHED();
   return nullptr;
 }
 
 RefPtr<WebTaskRunner> TaskRunnerHelper::Get(TaskType type, Document* document) {
+  DCHECK(!document || document->IsContextThread());
   return Get(type, document ? document->GetFrame() : nullptr);
 }
 
 RefPtr<WebTaskRunner> TaskRunnerHelper::Get(
     TaskType type,
-    ExecutionContext* executionContext) {
-  if (!executionContext)
-    return Get(type, ToDocument(executionContext));
-  if (executionContext->IsDocument())
-    return Get(type, ToDocument(executionContext));
-  if (executionContext->IsWorkerOrWorkletGlobalScope())
-    return Get(type, ToWorkerOrWorkletGlobalScope(executionContext));
-  executionContext = nullptr;
-  return Get(type, ToDocument(executionContext));
+    ExecutionContext* execution_context) {
+  DCHECK(!execution_context || execution_context->IsContextThread());
+  if (!execution_context || execution_context->IsDocument())
+    return Get(type, ToDocument(execution_context));
+  DCHECK(execution_context->IsWorkerOrWorkletGlobalScope());
+  return Get(type, ToWorkerOrWorkletGlobalScope(execution_context));
 }
 
 RefPtr<WebTaskRunner> TaskRunnerHelper::Get(TaskType type,
                                             ScriptState* script_state) {
   return Get(type,
              script_state ? ExecutionContext::From(script_state) : nullptr);
 }
 
 RefPtr<WebTaskRunner> TaskRunnerHelper::Get(
     TaskType type,
@@ skipping 33 matching lines @@
       // TODO(nhiroki): Identify which tasks can be throttled / suspendable and
       // move them into other task runners. See also comments in
       // Get(LocalFrame). (https://crbug.com/670534)
       return worker_thread->GetGlobalScopeScheduler()->UnthrottledTaskRunner();
   }
   NOTREACHED();
   return nullptr;
 }
 
 }  // namespace blink