Issue 1669 - Report blocked object subrequests as failed, not as empty HTML

src/plugin/PluginWbPassThrough.cpp

Index: src/plugin/PluginWbPassThrough.cpp
===================================================================
--- a/src/plugin/PluginWbPassThrough.cpp
+++ b/src/plugin/PluginWbPassThrough.cpp
@@ -363,7 +363,14 @@
     // Don't notify the client about aborting of the operation, thus don't call BaseClass::ReportResult.
     // Current method is called by the original protocol implementation and we are intercepting the
     // call here and eating it, we will call the proper ReportResult later by ourself.
-    return S_OK;
+    // NOTE: Feeding custom HTML to Flash, instead of original object subrequest
+    // doesn't have much sense. It also can manifest in unwanted result
+    // like video being blocked (See https://issues.adblockplus.org/ticket/1669)
+    // So we report blocked object subrequests as failed, not just empty HTML.
+    if (m_contentType != CFilter::contentTypeObjectSubrequest)
+    {
+      return S_OK;
+    }
   }
   return BaseClass::ReportResult(hrResult, dwError, szResult);
 }