Add ability to enqueue SharedFunctionInfos so they can run on bg threads

src/compiler-dispatcher/compiler-dispatcher.cc

 // Copyright 2016 the V8 project 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 "src/compiler-dispatcher/compiler-dispatcher.h"
 
 #include "include/v8-platform.h"
 #include "include/v8.h"
 #include "src/base/platform/time.h"
 #include "src/cancelable-task.h"
@@ skipping 244 matching lines @@
 
   std::unique_ptr<CompilerDispatcherJob> job(new CompilerDispatcherJob(
       isolate_, tracer_.get(), function, max_stack_size_));
   std::pair<int, int> key(Script::cast(function->script())->id(),
                           function->function_literal_id());
   jobs_.insert(std::make_pair(key, std::move(job)));
   ScheduleIdleTaskIfNeeded();
   return true;
 }
 
+bool CompilerDispatcher::EnqueueAndStep(Handle<SharedFunctionInfo> function) {
+  if (!Enqueue(function)) return false;
+
+  if (trace_compiler_dispatcher_) {
+    PrintF("CompilerDispatcher: stepping ");
+    function->ShortPrint();
+    PrintF("\n");
+  }
+  JobMap::const_iterator job = GetJobFor(function);
+  DoNextStepOnMainThread(isolate_, job->second.get(),
+                         ExceptionHandling::kSwallow);
+  ConsiderJobForBackgroundProcessing(job->second.get());
+  return true;
+}
+
 bool CompilerDispatcher::IsEnabled() const {
   v8::Isolate* v8_isolate = reinterpret_cast<v8::Isolate*>(isolate_);
   return FLAG_compiler_dispatcher && platform_->IdleTasksEnabled(v8_isolate);
 }
 
 bool CompilerDispatcher::IsEnqueued(Handle<SharedFunctionInfo> function) const {
   return GetJobFor(function) != jobs_.end();
 }
 
 void CompilerDispatcher::WaitForJobIfRunningOnBackground(
@@ skipping 332 matching lines @@
       lock.reset();
       DoNextStepOnMainThread(isolate_, job->second.get(),
                              ExceptionHandling::kSwallow);
     }
   }
   if (jobs_.size() > too_long_jobs) ScheduleIdleTaskIfNeeded();
 }
 
 }  // namespace internal
 }  // namespace v8