[android_webview] Don't block the IO thread when reading from an InputStream.

android_webview/native/android_stream_reader_url_request_job.h

Index: android_webview/native/android_stream_reader_url_request_job.h
diff --git a/android_webview/native/android_stream_reader_url_request_job.h b/android_webview/native/android_stream_reader_url_request_job.h
index e29acd86e90045dfcb2265d78d2d80fc217e9c53..f1b3595582f7dfbb21503a5d28e93f5f3a1b2d9c 100644
--- a/android_webview/native/android_stream_reader_url_request_job.h
+++ b/android_webview/native/android_stream_reader_url_request_job.h
@@ -6,12 +6,18 @@
 #define ANDROID_WEBVIEW_NATIVE_ANDROID_STREAM_READER_URL_REQUEST_JOB_H_
 
 #include "base/android/scoped_java_ref.h"
+#include "base/location.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "base/threading/non_thread_safe.h"
 #include "net/http/http_byte_range.h"
 #include "net/url_request/url_request_job.h"
 
+namespace android_webview {
+class InputStream;
+class InputStreamReader;
+}
+
 namespace net {
 class URLRequest;
 }
@@ -25,20 +31,20 @@ class AndroidStreamReaderURLRequestJob : public net::URLRequestJob {
    */
   class Delegate {
    public:
-    virtual base::android::ScopedJavaLocalRef<jobject> OpenInputStream(
+    virtual scoped_ptr<android_webview::InputStream> OpenInputStream(
         JNIEnv* env,
         net::URLRequest* request) = 0;
 
     virtual bool GetMimeType(
         JNIEnv* env,
         net::URLRequest* request,
-        jobject stream,
+        const android_webview::InputStream& stream,
         std::string* mime_type) = 0;
 
     virtual bool GetCharset(
         JNIEnv* env,
         net::URLRequest* request,
-        jobject stream,
+        const android_webview::InputStream& stream,
         std::string* charset) = 0;
 
     virtual ~Delegate() {}
@@ -51,6 +57,7 @@ class AndroidStreamReaderURLRequestJob : public net::URLRequestJob {
 
   // URLRequestJob:
   virtual void Start() OVERRIDE;
+  virtual void Kill() OVERRIDE;
   virtual bool ReadRawData(net::IOBuffer* buf,
                            int buf_size,
                            int* bytes_read) OVERRIDE;
@@ -62,24 +69,28 @@ class AndroidStreamReaderURLRequestJob : public net::URLRequestJob {
  protected:
   virtual ~AndroidStreamReaderURLRequestJob();
 
- private:
-  // Verify the requested range against the stream size.
-  bool VerifyRequestedRange(JNIEnv* env);
+  // Posts the |task| to the background worker thread.
+  // Useful to override in tests.
+  virtual void PostToWorkerThread(const tracked_objects::Location& from_here,
+                                  const base::Closure& task);
 
-  // Skip to the first byte of the requested read range.
-  bool SkipToRequestedRange(JNIEnv* env);
+  // Creates an InputStreamReader instance.
+  virtual android_webview::InputStreamReader*
+      CreateStreamReader(android_webview::InputStream* stream);
 
+ private:
   void StartAsync();
 
+  void OnReaderSeekCompleted(int content_size);
+  void OnReaderReadCompleted(int bytes_read);
+
   net::HttpByteRange byte_range_;
   scoped_ptr<Delegate> delegate_;
-  base::android::ScopedJavaGlobalRef<jobject> stream_;
-  base::android::ScopedJavaGlobalRef<jbyteArray> buffer_;
+  android_webview::InputStreamReader* input_stream_reader_;
+  scoped_ptr<android_webview::InputStream> stream_;
   base::WeakPtrFactory<AndroidStreamReaderURLRequestJob> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(AndroidStreamReaderURLRequestJob);
 };
 
-bool RegisterAndroidStreamReaderUrlRequestJob(JNIEnv* env);
-
 #endif  // ANDROID_WEBVIEW_NATIVE_ANDROID_STREAM_READER_URL_REQUEST_JOB_H_