Reland: URLRequestJob: change ReadRawData contract

content/browser/service_worker/service_worker_read_from_cache_job.cc

Index: content/browser/service_worker/service_worker_read_from_cache_job.cc
diff --git a/content/browser/service_worker/service_worker_read_from_cache_job.cc b/content/browser/service_worker/service_worker_read_from_cache_job.cc
index 93579911aeb1a0b95da449c6e0daa1be2c3d631d..6aa92af82bdd88625e8c8ca4b25e4bbaccddef36 100644
--- a/content/browser/service_worker/service_worker_read_from_cache_job.cc
+++ b/content/browser/service_worker/service_worker_read_from_cache_job.cc
@@ -41,26 +41,9 @@ ServiceWorkerReadFromCacheJob::~ServiceWorkerReadFromCacheJob() {
 }
 
 void ServiceWorkerReadFromCacheJob::Start() {
-  TRACE_EVENT_ASYNC_BEGIN1("ServiceWorker",
-                           "ServiceWorkerReadFromCacheJob::ReadInfo", this,
-                           "URL", request_->url().spec());
-  if (!context_) {
-    NotifyStartError(
-        net::URLRequestStatus(net::URLRequestStatus::FAILED, net::ERR_FAILED));
-    return;
-  }
-
-  // Create a response reader and start reading the headers,
-  // we'll continue when thats done.
-  if (is_main_script())
-    version_->embedded_worker()->OnScriptReadStarted();
-  reader_ = context_->storage()->CreateResponseReader(resource_id_);
-  http_info_io_buffer_ = new HttpResponseInfoIOBuffer;
-  reader_->ReadInfo(
-      http_info_io_buffer_.get(),
-      base::Bind(&ServiceWorkerReadFromCacheJob::OnReadInfoComplete,
-                 weak_factory_.GetWeakPtr()));
-  SetStatus(net::URLRequestStatus(net::URLRequestStatus::IO_PENDING, 0));
+  base::ThreadTaskRunnerHandle::Get()->PostTask(
+      FROM_HERE, base::Bind(&ServiceWorkerReadFromCacheJob::StartAsync,
+                            weak_factory_.GetWeakPtr()));
 }
 
 void ServiceWorkerReadFromCacheJob::Kill() {
@@ -122,11 +105,9 @@ void ServiceWorkerReadFromCacheJob::SetExtraRequestHeaders(
     range_requested_ = ranges[0];
 }
 
-bool ServiceWorkerReadFromCacheJob::ReadRawData(net::IOBuffer* buf,
-                                                int buf_size,
-                                                int* bytes_read) {
+int ServiceWorkerReadFromCacheJob::ReadRawData(net::IOBuffer* buf,
+                                               int buf_size) {
   DCHECK_NE(buf_size, 0);
-  DCHECK(bytes_read);
   DCHECK(!reader_->IsReadPending());
   TRACE_EVENT_ASYNC_BEGIN1("ServiceWorker",
                            "ServiceWorkerReadFromCacheJob::ReadRawData",
@@ -135,8 +116,31 @@ bool ServiceWorkerReadFromCacheJob::ReadRawData(net::IOBuffer* buf,
   reader_->ReadData(buf, buf_size,
                     base::Bind(&ServiceWorkerReadFromCacheJob::OnReadComplete,
                                weak_factory_.GetWeakPtr()));
+  return net::ERR_IO_PENDING;
+}
+
+void ServiceWorkerReadFromCacheJob::StartAsync() {
+  TRACE_EVENT_ASYNC_BEGIN1("ServiceWorker",
+                           "ServiceWorkerReadFromCacheJob::ReadInfo", this,
+                           "URL", request_->url().spec());
+  if (!context_) {
+    // NotifyStartError is not safe to call synchronously in Start.
+    NotifyStartError(
+        net::URLRequestStatus(net::URLRequestStatus::FAILED, net::ERR_FAILED));
+    return;
+  }
+
+  // Create a response reader and start reading the headers,
+  // we'll continue when thats done.
+  if (is_main_script())
+    version_->embedded_worker()->OnScriptReadStarted();
+  reader_ = context_->storage()->CreateResponseReader(resource_id_);
+  http_info_io_buffer_ = new HttpResponseInfoIOBuffer;
+  reader_->ReadInfo(
+      http_info_io_buffer_.get(),
+      base::Bind(&ServiceWorkerReadFromCacheJob::OnReadInfoComplete,
+                 weak_factory_.GetWeakPtr()));
   SetStatus(net::URLRequestStatus(net::URLRequestStatus::IO_PENDING, 0));
-  return false;
 }
 
 const net::HttpResponseInfo* ServiceWorkerReadFromCacheJob::http_info() const {
@@ -154,6 +158,8 @@ void ServiceWorkerReadFromCacheJob::OnReadInfoComplete(int result) {
     ServiceWorkerMetrics::CountReadResponseResult(
         ServiceWorkerMetrics::READ_HEADERS_ERROR);
     Done(net::URLRequestStatus(net::URLRequestStatus::FAILED, result));
+    NotifyStartError(
+        net::URLRequestStatus(net::URLRequestStatus::FAILED, result));
     return;
   }
   DCHECK_GE(result, 0);
@@ -207,23 +213,22 @@ void ServiceWorkerReadFromCacheJob::Done(const net::URLRequestStatus& status) {
   }
   if (is_main_script())
     version_->embedded_worker()->OnScriptReadFinished();
-  NotifyDone(status);
 }
 
 void ServiceWorkerReadFromCacheJob::OnReadComplete(int result) {
   ServiceWorkerMetrics::ReadResponseResult check_result;
-  if (result == 0) {
+
+  if (result >= 0) {
     check_result = ServiceWorkerMetrics::READ_OK;
-    Done(net::URLRequestStatus());
-  } else if (result < 0) {
+    if (result == 0)
+      Done(net::URLRequestStatus());
+  } else {
     check_result = ServiceWorkerMetrics::READ_DATA_ERROR;
     Done(net::URLRequestStatus(net::URLRequestStatus::FAILED, result));
-  } else {
-    check_result = ServiceWorkerMetrics::READ_OK;
-    SetStatus(net::URLRequestStatus());  // Clear the IO_PENDING status
   }
+
   ServiceWorkerMetrics::CountReadResponseResult(check_result);
-  NotifyReadComplete(result);
+  ReadRawDataComplete(result);
   TRACE_EVENT_ASYNC_END1("ServiceWorker",
                          "ServiceWorkerReadFromCacheJob::ReadRawData",
                          this,