Bugfix for cross-origin check

The code is mistaking a missing reader for an error, but readers are now destroyed and re-created on demand.
Adding a new variable to explicitly track failures fixes the problem.

BUG=639690

Review-Url: https://codereview.chromium.org/2271313002
Cr-Commit-Position: refs/heads/master@{#414218}

media/blink/multibuffer_data_source.cc

@@ -113,6 +113,7 @@ MultibufferDataSource::MultibufferDataSource(
       total_bytes_(kPositionNotSpecified),
       streaming_(false),
       loading_(false),
+      failed_(false),
       render_task_runner_(task_runner),
       url_index_(url_index),
       frame_(frame),
@@ -185,6 +186,7 @@ void MultibufferDataSource::OnRedirect(
     const scoped_refptr<UrlData>& destination) {
   if (!destination) {
     // A failure occured.
+    failed_ = true;
     if (!init_cb_.is_null()) {
       render_task_runner_->PostTask(
           FROM_HERE,
@@ -256,8 +258,7 @@ bool MultibufferDataSource::DidPassCORSAccessCheck() const {
   // If init_cb is set, we initialization is not finished yet.
   if (!init_cb_.is_null())
     return false;
-  // Loader will be false if there was a failure.
-  if (!reader_)
+  if (failed_)
     return false;
   return true;
 }

media/blink/multibuffer_data_source.h

@@ -174,6 +174,9 @@ class MEDIA_BLINK_EXPORT MultibufferDataSource
   // |downloading_cb_|.
   bool loading_;
 
+  // True if a failure has occured.
+  bool failed_;
+
   // The task runner of the render thread.
   const scoped_refptr<base::SingleThreadTaskRunner> render_task_runner_;
 

media/blink/multibuffer_data_source_unittest.cc

@@ -1448,4 +1448,34 @@ TEST_F(MultibufferDataSourceTest, FileSizeLessThanBlockSize) {
   Stop();
 }
 
+TEST_F(MultibufferDataSourceTest, DidPassCORSAccessTest) {
+  InitializeWithCORS(kHttpUrl, true, UrlData::CORS_ANONYMOUS);
+  set_preload(MultibufferDataSource::NONE);
+  WebURLResponse response1 =
+      response_generator_->GeneratePartial206(0, kDataSize - 1);
+  response1.setWasFetchedViaServiceWorker(true);
+  response1.setOriginalURLViaServiceWorker(GURL(kHttpDifferentOriginUrl));
+  WebURLResponse response2 =
+      response_generator_->GeneratePartial206(kDataSize, kDataSize * 2 - 1);
+
+  EXPECT_CALL(host_, SetTotalBytes(kFileSize));
+  EXPECT_CALL(host_, AddBufferedByteRange(0, kDataSize));
+  EXPECT_CALL(*this, ReadCallback(kDataSize));
+
+  EXPECT_FALSE(data_source_->DidPassCORSAccessCheck());
+  Respond(response1);
+  ReceiveData(kDataSize);
+  ReadAt(0);
+  EXPECT_TRUE(loading());
+  EXPECT_TRUE(data_source_->DidPassCORSAccessCheck());
+
+  FinishLoading();
+
+  // Verify that if reader_ is null, DidPassCORSAccessCheck still returns true.
+  data_source_->Stop();
+  base::RunLoop().RunUntilIdle();
+
+  EXPECT_TRUE(data_source_->DidPassCORSAccessCheck());
+}
+
 }  // namespace media