[Android WebView] Call shouldInterceptRequest on a background thread

android_webview/browser/net/android_stream_reader_url_request_job.h

 // Copyright (c) 2012 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.
 
-#ifndef ANDROID_WEBVIEW_NATIVE_ANDROID_STREAM_READER_URL_REQUEST_JOB_H_
-#define ANDROID_WEBVIEW_NATIVE_ANDROID_STREAM_READER_URL_REQUEST_JOB_H_
+#ifndef ANDROID_WEBVIEW_BROWSER_NET_ANDROID_STREAM_READER_URL_REQUEST_JOB_H_
+#define ANDROID_WEBVIEW_BROWSER_NET_ANDROID_STREAM_READER_URL_REQUEST_JOB_H_
 
 #include <string>
 
 #include "base/android/scoped_java_ref.h"
+#include "base/callback.h"
 #include "base/location.h"
+#include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "base/threading/thread_checker.h"
 #include "net/http/http_byte_range.h"
 #include "net/url_request/url_request_job.h"
 
 namespace base {
 class TaskRunner;
 }
@@ skipping 12 matching lines @@
 
 // A request job that reads data from a Java InputStream.
 class AndroidStreamReaderURLRequestJob : public net::URLRequestJob {
  public:
   /*
    * We use a delegate so that we can share code for this job in slightly
    * different contexts.
    */
   class Delegate {
    public:
+    virtual ~Delegate() {}
+
     // This method is called from a worker thread, not from the IO thread.
     virtual scoped_ptr<android_webview::InputStream> OpenInputStream(
         JNIEnv* env,
         const GURL& url) = 0;
 
     // This method is called on the Job's thread if the result of calling
     // OpenInputStream was null.
     // Setting the |restart| parameter to true will cause the request to be
     // restarted with a new job.
     virtual void OnInputStreamOpenFailed(
         net::URLRequest* request,
         bool* restart) = 0;
 
     virtual bool GetMimeType(
         JNIEnv* env,
         net::URLRequest* request,
         android_webview::InputStream* stream,
         std::string* mime_type) = 0;
 
     virtual bool GetCharset(
         JNIEnv* env,
         net::URLRequest* request,
         android_webview::InputStream* stream,
         std::string* charset) = 0;
 
     virtual void AppendResponseHeaders(JNIEnv* env,
                                        net::HttpResponseHeaders* headers) = 0;
+  };
 
-    virtual ~Delegate() {}
+  class DelegateObtainer {
+   public:
+    virtual ~DelegateObtainer() {}
+
+    typedef base::Callback<void(scoped_ptr<Delegate>)> Callback;
+    virtual void ObtainDelegate(net::URLRequest* request,
+                                const Callback& callback) = 0;
   };
 
   AndroidStreamReaderURLRequestJob(
       net::URLRequest* request,
       net::NetworkDelegate* network_delegate,
       scoped_ptr<Delegate> delegate);
+  AndroidStreamReaderURLRequestJob(
+      net::URLRequest* request,
+      net::NetworkDelegate* network_delegate,
+      scoped_ptr<DelegateObtainer> delegate_obtainer,
+      bool); // resolve ambiguity
 
   // URLRequestJob:
   void Start() override;
   void Kill() override;
   bool ReadRawData(net::IOBuffer* buf, int buf_size, int* bytes_read) override;
   void SetExtraRequestHeaders(const net::HttpRequestHeaders& headers) override;
   bool GetMimeType(std::string* mime_type) const override;
   bool GetCharset(std::string* charset) override;
   int GetResponseCode() const override;
   void GetResponseInfo(net::HttpResponseInfo* info) override;
 
  protected:
   ~AndroidStreamReaderURLRequestJob() override;
 
   // Gets the TaskRunner for the worker thread.
   // Overridden in unittests.
   virtual base::TaskRunner* GetWorkerThreadRunner();
 
   // Creates an InputStreamReader instance.
   // Overridden in unittests to return a mock.
   virtual scoped_ptr<android_webview::InputStreamReader>
       CreateStreamReader(android_webview::InputStream* stream);
 
  private:
+  // Used as a callback when obtaining the delegate asynchronously,
+  // see DelegateObtainer.
+  void DelegateObtained(scoped_ptr<Delegate> delegate);
+  // Actual URLRequestJob::Start implementation.
+  void DoStart();
+
   void HeadersComplete(int status_code, const std::string& status_text);
 
   void OnInputStreamOpened(
       scoped_ptr<Delegate> delegate,
       scoped_ptr<android_webview::InputStream> input_stream);
   void OnReaderSeekCompleted(int content_size);
   void OnReaderReadCompleted(int bytes_read);
 
   net::HttpByteRange byte_range_;
   scoped_ptr<net::HttpResponseInfo> response_info_;
   scoped_ptr<Delegate> delegate_;
+  scoped_ptr<DelegateObtainer> delegate_obtainer_;
   scoped_refptr<InputStreamReaderWrapper> input_stream_reader_wrapper_;
   base::ThreadChecker thread_checker_;
 
   base::WeakPtrFactory<AndroidStreamReaderURLRequestJob> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(AndroidStreamReaderURLRequestJob);
 };
 
 }  // namespace android_webview
 
-#endif  // ANDROID_WEBVIEW_NATIVE_ANDROID_STREAM_READER_URL_REQUEST_JOB_H_
+#endif  // ANDROID_WEBVIEW_BROWSER_NET_ANDROID_STREAM_READER_URL_REQUEST_JOB_H_