[MSE][GStreamer] update maximum buffer size after receiving first init segment

https://bugs.webkit.org/show_bug.cgi?id=296059

Reviewed by Xabier Rodriguez-Calvar.

The current
SourceBuffer::sourceBufferPrivateDidReceiveInitializationSegment() code
only calls SourceBufferPrivate::setMaximumBufferSize() on new init
segments when the segment has (at least) a video track. Maximum buffer
size is managed with high granularity in WPE by using the
MSE_MAX_BUFFER_SIZE environment variable. For that reason, that call
must happen independently of the kind of tracks present (at least on the
WPE platform). This will ensure that the proper frame eviction code in
SourceBufferPrivate::setMaximumBufferSize() is called in all cases.

See: #1534

This patch calls SourceBufferPrivate::setMaximumBufferSize()
inconditionally on the WPE platform.

Original author: Eugene Mutavchi <Ievgen_Mutavchi@comcast.com>

* Source/WebCore/Modules/mediasource/SourceBuffer.cpp:
(WebCore::SourceBuffer::sourceBufferPrivateDidReceiveInitializationSegment): Disable the if, so the call happens inconditionally on WPE.

Canonical link: https://commits.webkit.org/297674@main

Author: emutavchi

Source/WebCore/Modules/mediasource/SourceBuffer.cpp

@@ -1042,7 +1042,9 @@ Ref<MediaPromise> SourceBuffer::sourceBufferPrivateDidReceiveInitializationSegme
         // 5.6 Set first initialization segment flag to true.
         m_receivedFirstInitializationSegment = true;
 
+#if !PLATFORM(WPE)
         if (hasVideo())
+#endif
             m_private->setMaximumBufferSize(maximumBufferSize());
     }