media: Make sure we transition back to a non-loading state

media/blink/multibuffer_data_source.cc

 // Copyright 2013 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.
 
 #include "media/blink/multibuffer_data_source.h"
 
 #include <utility>
 
 #include "base/bind.h"
 #include "base/callback_helpers.h"
@@ skipping 398 matching lines @@
       // fail like they would if we had known the file size at the beginning.
       total_bytes_ = reader_->Tell();
       if (total_bytes_ != kPositionNotSpecified)
         host_->SetTotalBytes(total_bytes_);
     }
 
     ReadOperation::Run(std::move(read_op_), bytes_read);
   } else {
     reader_->Wait(1, base::Bind(&MultibufferDataSource::ReadTask,
                                 weak_factory_.GetWeakPtr()));
-    UpdateLoadingState_Locked(false);
   }
+  UpdateLoadingState_Locked(false);
 }
 
 void MultibufferDataSource::StopInternal_Locked() {
   lock_.AssertAcquired();
   if (stop_signal_received_)
     return;
 
   stop_signal_received_ = true;
 
   // Initialize() isn't part of the DataSource interface so don't call it in
@@ skipping 100 matching lines @@
   UpdateLoadingState_Locked(false);
 }
 
 void MultibufferDataSource::UpdateLoadingState_Locked(bool force_loading) {
   DVLOG(1) << __func__;
   lock_.AssertAcquired();
   if (assume_fully_buffered())
     return;
   // Update loading state.
   bool is_loading = !!reader_ && reader_->IsLoading();
-  if (read_op_)
-    is_loading = true;
   if (force_loading || is_loading != loading_) {
-    loading_ = is_loading || force_loading;
+    bool loading = is_loading || force_loading;
 
-    if (!loading_ && cancel_on_defer_) {
+    if (!loading && cancel_on_defer_) {
+      if (read_op_) {
+        // We can't destroy the reader if a read operation is pending.
+        // UpdateLoadingState_Locked will be called again when the read
+        // operation is done.
+        return;
+      }
       reader_.reset(nullptr);
     }
 
+    loading_ = loading;
+
     // Callback could kill us, be sure to call it last.
     downloading_cb_.Run(loading_);
   }
 }
 
 void MultibufferDataSource::UpdateBufferSizes() {
   DVLOG(1) << __func__;
   if (!reader_)
     return;
 
@@ skipping 41 matching lines @@
   reader_->SetPinRange(back_buffer, kMaxBufferPreload + kPreloadHighExtra);
 
   if (preload_ == METADATA) {
     reader_->SetPreload(0, 0);
   } else {
     reader_->SetPreload(preload_high, preload);
   }
 }
 
 }  // namespace media