UPGRADING and UPGRADING.INTERNALS for SVG and extensible image API

Author: ndossche

UPGRADING

@@ -92,6 +92,11 @@ PHP 8.5 UPGRADE NOTES
 - DOM:
   . Added Dom\Element::$outerHTML.
 
+- Standard:
+  . getimagesize() now supports SVG images when ext-libxml is also loaded.
+    Similarly, image_type_to_extension() and image_type_to_extension()
+    now also handle IMAGETYPE_SVG.
+
 - XSL:
   . The $namespace argument of XSLTProcessor::getParameter(),
     XSLTProcessor::setParameter() and XSLTProcessor::removeParameter()
@@ -261,6 +266,9 @@ PHP 8.5 UPGRADE NOTES
   . TCP_BBR_ALGORITHM (FreeBSD only).
   . AF_PACKET (Linux only).
 
+- Standard:
+  . IMAGETYPE_SVG when libxml is loaded.
+
 ========================================
 11. Changes to INI File Handling
 ========================================

UPGRADING.INTERNALS

@@ -53,6 +53,12 @@ PHP 8.5 INTERNALS UPGRADE NOTES
     is still valid. This is useful when a GC cycle is collected and the
     database object can be destroyed prior to destroying the statement.
 
+- ext/standard:
+  . The functionality of getimagesize(), image_type_to_mime_type(),
+    and image_type_to_extension() is now extensible using the internal APIs
+    php_image_register_handler() and php_image_unregister_handler() in
+    php_image.h.
+
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 4. OpCode changes
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