Merge r223168 - [GStreamer] Fix double seek requested by downloadbuff…

…er GStreamer element in webkibwebsrc

https://bugs.webkit.org/show_bug.cgi?id=178079

Reviewed by Žan Doberšek.

When the downloadbuffer GStreamer element requests two seeks too
close to each other there's some rare race condition where our
source answers that it is not seekable and ends up with
downloadbuffer element to seek beyond the file size, which causes
the server to issue a 416 HTTP error code eventually, causing our
MediaPlayer to stop.

* platform/graphics/gstreamer/WebKitWebSourceGStreamer.cpp:
(webKitWebSrcStop): We only unset he seekable attribute if we are
not seeking.

Source/WebCore/ChangeLog

@@ -1,3 +1,21 @@
+2017-10-10  Xabier Rodriguez Calvar  <calvaris@igalia.com>
+
+        [GStreamer] Fix double seek requested by downloadbuffer GStreamer element in webkibwebsrc
+        https://bugs.webkit.org/show_bug.cgi?id=178079
+
+        Reviewed by Žan Doberšek.
+
+        When the downloadbuffer GStreamer element requests two seeks too
+        close to each other there's some rare race condition where our
+        source answers that it is not seekable and ends up with
+        downloadbuffer element to seek beyond the file size, which causes
+        the server to issue a 416 HTTP error code eventually, causing our
+        MediaPlayer to stop.
+
+        * platform/graphics/gstreamer/WebKitWebSourceGStreamer.cpp:
+        (webKitWebSrcStop): We only unset he seekable attribute if we are
+        not seeking.
+
 2017-10-10  Joanmarie Diggs  <jdiggs@igalia.com>
 
         AX: [ATK] ARIA form role should be mapped to ATK_ROLE_LANDMARK; not ATK_ROLE_FORM

Source/WebCore/platform/graphics/gstreamer/WebKitWebSourceGStreamer.cpp

@@ -58,7 +58,7 @@ class CachedResourceStreamingClient final : public PlatformMediaResourceClient {
     virtual ~CachedResourceStreamingClient();
 private:
 #if USE(SOUP)
-    char* getOrCreateReadBuffer(PlatformMediaResource&, size_t requestedSize, size_t& actualSize);
+    char* getOrCreateReadBuffer(PlatformMediaResource&, size_t requestedSize, size_t& actualSize) override;
 #endif
     // PlatformMediaResourceClient virtual methods.
     void responseReceived(PlatformMediaResource&, const ResourceResponse&) override;
@@ -373,12 +373,12 @@ static void webKitWebSrcStop(WebKitWebSrc* src)
     priv->paused = false;
 
     priv->offset = 0;
-    priv->seekable = FALSE;
 
     if (!wasSeeking) {
         priv->size = 0;
         priv->requestedOffset = 0;
         priv->player = nullptr;
+        priv->seekable = FALSE;
     }
 
     if (priv->appsrc) {