Split content script injections into multiple tasks

extensions/renderer/script_injection_manager.cc

 // Copyright 2014 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 "extensions/renderer/script_injection_manager.h"
 
 #include <memory>
 #include <utility>
 
 #include "base/auto_reset.h"
 #include "base/bind.h"
 #include "base/memory/ptr_util.h"
 #include "base/memory/weak_ptr.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "base/values.h"
 #include "content/public/common/browser_side_navigation_policy.h"
 #include "content/public/renderer/render_frame.h"
 #include "content/public/renderer/render_frame_observer.h"
 #include "content/public/renderer/render_thread.h"
 #include "extensions/common/extension.h"
 #include "extensions/common/extension_messages.h"
 #include "extensions/common/extension_set.h"
+#include "extensions/common/feature_switch.h"
 #include "extensions/renderer/extension_frame_helper.h"
 #include "extensions/renderer/extension_injection_host.h"
 #include "extensions/renderer/programmatic_script_injector.h"
 #include "extensions/renderer/renderer_extension_registry.h"
 #include "extensions/renderer/script_injection.h"
 #include "extensions/renderer/scripts_run_info.h"
 #include "extensions/renderer/web_ui_injection_host.h"
 #include "ipc/ipc_message_macros.h"
 #include "third_party/WebKit/public/platform/WebURLError.h"
 #include "third_party/WebKit/public/web/WebDocument.h"
@@ skipping 149 matching lines @@
   // whereas DidFinishLoad corresponds to completing the document and all
   // subresources' load. We don't want to hold up script injection for a
   // particularly slow subresource, so we set a delayed task from here - but if
   // we finish everything before that point (i.e., DidFinishLoad() is
   // triggered), then there's no reason to keep waiting.
   base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
       FROM_HERE,
       base::Bind(&ScriptInjectionManager::RFOHelper::RunIdle,
                  weak_factory_.GetWeakPtr()),
       base::TimeDelta::FromMilliseconds(kScriptIdleTimeoutInMs));
+
+  if (FeatureSwitch::yield_between_content_script_runs()->IsEnabled()) {
+    ExtensionFrameHelper::Get(render_frame())
+        ->ScheduleAtDocumentIdle(
+            base::Bind(&ScriptInjectionManager::RFOHelper::RunIdle,
+                       weak_factory_.GetWeakPtr()));
+  }
 }
 
 void ScriptInjectionManager::RFOHelper::DidFinishLoad() {
   DCHECK(content::RenderThread::Get());
-  // Ensure that we don't block any UI progress by running scripts.
-  base::ThreadTaskRunnerHandle::Get()->PostTask(
-      FROM_HERE,
-      base::Bind(&ScriptInjectionManager::RFOHelper::RunIdle,
-                 weak_factory_.GetWeakPtr()));
+  if (!FeatureSwitch::yield_between_content_script_runs()->IsEnabled()) {
+    // Ensure that we don't block any UI progress by running scripts.
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
+        FROM_HERE, base::Bind(&ScriptInjectionManager::RFOHelper::RunIdle,
+                              weak_factory_.GetWeakPtr()));
+  }
 }
 
 void ScriptInjectionManager::RFOHelper::FrameDetached() {
   // The frame is closing - invalidate.
   InvalidateAndResetFrame();
 }
 
 void ScriptInjectionManager::RFOHelper::OnDestruct() {
   manager_->RemoveObserver(this);
 }
@@ skipping 303 matching lines @@
   ScriptsRunInfo scripts_run_info(injection->render_frame(),
                                   UserScript::RUN_DEFERRED);
   ScriptInjection::InjectionResult res = injection->OnPermissionGranted(
       &scripts_run_info);
   if (res == ScriptInjection::INJECTION_BLOCKED)
     running_injections_.push_back(std::move(injection));
   scripts_run_info.LogRun(activity_logging_enabled_);
 }
 
 }  // namespace extensions