Improve retry support for media network loading.

Retry 30 times in 30 seconds instead of 3 times in 750ms.
The retries are spaced so that the first retry is 250ms, second is 300ms, then 350ms, etc.

BUG=592703

Review URL: https://codereview.chromium.org/1777153002

Cr-Commit-Position: refs/heads/master@{#380723}
(cherry picked from commit 018c484)

Review URL: https://codereview.chromium.org/1796973004 .

Cr-Commit-Position: refs/branch-heads/2661@{crosswalk-project#227}
Cr-Branched-From: ef6f6ae-refs/heads/master@{#378081}

media/blink/buffered_data_source.cc

@@ -23,13 +23,16 @@ namespace {
 // of FFmpeg.
 const int kInitialReadBufferSize = 32768;
 
-// Number of cache misses or read failures we allow for a single Read() before
-// signaling an error.
-const int kLoaderRetries = 3;
-
 // The number of milliseconds to wait before retrying a failed load.
 const int kLoaderFailedRetryDelayMs = 250;
 
+// Each retry, add this many MS to the delay.
+// total delay is:
+// (kLoaderPartialRetryDelayMs +
+//  kAdditionalDelayPerRetryMs * (kMaxRetries - 1) / 2) * kLoaderRetries
+//  = 29250 ms
+const int kAdditionalDelayPerRetryMs = 50;
+
 }  // namespace
 
 namespace media {
@@ -491,7 +494,9 @@ void BufferedDataSource::ReadCallback(
             FROM_HERE, base::Bind(&BufferedDataSource::ReadCallback,
                                   weak_factory_.GetWeakPtr(),
                                   BufferedResourceLoader::kCacheMiss, 0),
-            base::TimeDelta::FromMilliseconds(kLoaderFailedRetryDelayMs));
+            base::TimeDelta::FromMilliseconds(kLoaderFailedRetryDelayMs +
+                                              read_op_->retries() *
+                                                  kAdditionalDelayPerRetryMs));
         return;
       }
 

media/blink/buffered_data_source.h

@@ -122,6 +122,9 @@ class BufferedDataSourceInterface : public DataSource {
 class MEDIA_BLINK_EXPORT BufferedDataSource
     : NON_EXPORTED_BASE(public BufferedDataSourceInterface) {
  public:
+  // Number of cache misses or read failures we allow for a single Read() before
+  // signaling an error.
+  enum { kLoaderRetries = 30 };
   typedef base::Callback<void(bool)> DownloadingCB;
 
   // |url| and |cors_mode| are passed to the object. Buffered byte range changes

media/blink/buffered_data_source_unittest.cc

@@ -633,18 +633,11 @@ TEST_F(BufferedDataSourceTest, Http_TooManyRetries) {
   // Make sure there's a pending read -- we'll expect it to error.
   ReadAt(0);
 
-  // It'll try three times.
-  ExpectCreateResourceLoader();
-  FinishLoading();
-  Respond(response_generator_->Generate206(0));
-
-  ExpectCreateResourceLoader();
-  FinishLoading();
-  Respond(response_generator_->Generate206(0));
-
-  ExpectCreateResourceLoader();
-  FinishLoading();
-  Respond(response_generator_->Generate206(0));
+  for (int i = 0; i < BufferedDataSource::kLoaderRetries; i++) {
+    ExpectCreateResourceLoader();
+    FinishLoading();
+    Respond(response_generator_->Generate206(0));
+  }
 
   // It'll error after this.
   EXPECT_CALL(*this, ReadCallback(media::DataSource::kReadError));
@@ -660,18 +653,11 @@ TEST_F(BufferedDataSourceTest, File_TooManyRetries) {
   // Make sure there's a pending read -- we'll expect it to error.
   ReadAt(0);
 
-  // It'll try three times.
-  ExpectCreateResourceLoader();
-  FinishLoading();
-  Respond(response_generator_->GenerateFileResponse(0));
-
-  ExpectCreateResourceLoader();
-  FinishLoading();
-  Respond(response_generator_->GenerateFileResponse(0));
-
-  ExpectCreateResourceLoader();
-  FinishLoading();
-  Respond(response_generator_->GenerateFileResponse(0));
+  for (int i = 0; i < BufferedDataSource::kLoaderRetries; i++) {
+    ExpectCreateResourceLoader();
+    FinishLoading();
+    Respond(response_generator_->GenerateFileResponse(0));
+  }
 
   // It'll error after this.
   EXPECT_CALL(*this, ReadCallback(media::DataSource::kReadError));

media/blink/multibuffer_data_source_unittest.cc

@@ -322,6 +322,12 @@ class MultibufferDataSourceTest : public testing::Test {
     message_loop_.RunUntilIdle();
   }
 
+  void FailLoading() {
+    data_provider()->didFail(url_loader(),
+                             response_generator_->GenerateError());
+    message_loop_.RunUntilIdle();
+  }
+
   void Restart() {
     EXPECT_TRUE(data_provider());
     EXPECT_FALSE(active_loader_allownull());
@@ -793,23 +799,19 @@ TEST_F(MultibufferDataSourceTest, Http_TooManyRetries) {
   // Make sure there's a pending read -- we'll expect it to error.
   ReadAt(kDataSize);
 
-  // It'll try three times.
-  FinishLoading();
-  Restart();
-  Respond(response_generator_->Generate206(kDataSize));
-
-  FinishLoading();
-  Restart();
-  Respond(response_generator_->Generate206(kDataSize));
-
-  FinishLoading();
-  Restart();
-  Respond(response_generator_->Generate206(kDataSize));
-
-  // It'll error after this.
-  EXPECT_CALL(*this, ReadCallback(media::DataSource::kReadError));
-  FinishLoading();
+  for (int i = 0; i < ResourceMultiBufferDataProvider::kMaxRetries; i++) {
+    FailLoading();
+    data_provider()->Start();
+    Respond(response_generator_->Generate206(kDataSize));
+  }
 
+  // Stop() will also cause the readback to be called with kReadError, but
+  // we want to make sure it was called during FailLoading().
+  bool failed_ = false;
+  EXPECT_CALL(*this, ReadCallback(media::DataSource::kReadError))
+      .WillOnce(Assign(&failed_, true));
+  FailLoading();
+  EXPECT_TRUE(failed_);
   EXPECT_FALSE(loading());
   Stop();
 }
@@ -820,23 +822,19 @@ TEST_F(MultibufferDataSourceTest, File_TooManyRetries) {
   // Make sure there's a pending read -- we'll expect it to error.
   ReadAt(kDataSize);
 
-  // It'll try three times.
-  FinishLoading();
-  Restart();
-  Respond(response_generator_->GenerateFileResponse(0));
-
-  FinishLoading();
-  Restart();
-  Respond(response_generator_->GenerateFileResponse(0));
-
-  FinishLoading();
-  Restart();
-  Respond(response_generator_->GenerateFileResponse(0));
-
-  // It'll error after this.
-  EXPECT_CALL(*this, ReadCallback(media::DataSource::kReadError));
-  FinishLoading();
+  for (int i = 0; i < ResourceMultiBufferDataProvider::kMaxRetries; i++) {
+    FailLoading();
+    data_provider()->Start();
+    Respond(response_generator_->Generate206(kDataSize));
+  }
 
+  // Stop() will also cause the readback to be called with kReadError, but
+  // we want to make sure it was called during FailLoading().
+  bool failed_ = false;
+  EXPECT_CALL(*this, ReadCallback(media::DataSource::kReadError))
+      .WillOnce(Assign(&failed_, true));
+  FailLoading();
+  EXPECT_TRUE(failed_);
   EXPECT_FALSE(loading());
   Stop();
 }

media/blink/resource_multibuffer_data_provider.cc

@@ -35,14 +35,19 @@ namespace media {
 // The number of milliseconds to wait before retrying a failed load.
 const int kLoaderFailedRetryDelayMs = 250;
 
+// Each retry, add this many MS to the delay.
+// total delay is:
+// (kLoaderPartialRetryDelayMs +
+//  kAdditionalDelayPerRetryMs * (kMaxRetries - 1) / 2) * kMaxretries = 29250 ms
+const int kAdditionalDelayPerRetryMs = 50;
+
 // The number of milliseconds to wait before retrying when the server
 // decides to not give us all the data at once.
 const int kLoaderPartialRetryDelayMs = 25;
 
 const int kHttpOK = 200;
 const int kHttpPartialContent = 206;
 const int kHttpRangeNotSatisfiable = 416;
-const int kMaxRetries = 3;
 
 ResourceMultiBufferDataProvider::ResourceMultiBufferDataProvider(
     UrlData* url_data,
@@ -411,12 +416,11 @@ void ResourceMultiBufferDataProvider::didFail(WebURLLoader* loader,
     base::MessageLoop::current()->PostDelayedTask(
         FROM_HERE, base::Bind(&ResourceMultiBufferDataProvider::Start,
                               weak_factory_.GetWeakPtr()),
-        base::TimeDelta::FromMilliseconds(kLoaderFailedRetryDelayMs));
+        base::TimeDelta::FromMilliseconds(
+            kLoaderFailedRetryDelayMs + kAdditionalDelayPerRetryMs * retries_));
   } else {
     // We don't need to continue loading after failure.
-    //
-    // Keep it alive until we exit this method so that |error| remains valid.
-    scoped_ptr<ActiveLoader> active_loader = std::move(active_loader_);
+    // Note that calling Fail() will most likely delete this object.
     url_data_->Fail();
   }
 }

media/blink/resource_multibuffer_data_provider.h

@@ -28,6 +28,9 @@ class MEDIA_BLINK_EXPORT ResourceMultiBufferDataProvider
     : NON_EXPORTED_BASE(public MultiBuffer::DataProvider),
       NON_EXPORTED_BASE(public blink::WebURLLoaderClient) {
  public:
+  // NUmber of times we'll retry if the connection fails.
+  enum { kMaxRetries = 30 };
+
   ResourceMultiBufferDataProvider(UrlData* url_data, MultiBufferBlockId pos);
   ~ResourceMultiBufferDataProvider() override;