Cherry-pick 270274@main (58df23f). https://bugs.webkit.org/show_bug.c…

…gi?id=260771

    REGRESSION(266247@main): PDF "Save" button does nothing, "Print" function also broken
    https://bugs.webkit.org/show_bug.cgi?id=260771

    Reviewed by Chris Dumez.

    The PDF.js viewer protocol and resource protocols both should be treated
    the same as HTTP protocols and have access to blob URLs. The protocol is
    an implementation detail that shouldn't affect how the web content
    behaves and certainly should not restrict access to web platform
    features.

    * Source/WebCore/page/SecurityOrigin.cpp:
    (WebCore::isSafelistedBlobProtocol):

    Canonical link: https://commits.webkit.org/270274@main

Source/WebCore/page/SecurityOrigin.cpp

@@ -178,6 +178,12 @@ inline bool isSafelistedBlobProtocol(const URL& url)
     // except that assert gets hit on certain tests.
     return url.protocolIsInHTTPFamily()
         || url.protocolIsFile()
+#if PLATFORM(GTK) || PLATFORM(WPE)
+        || url.protocolIs("resource"_s)
+#endif
+#if ENABLE(PDFJS)
+        || url.protocolIs("webkit-pdfjs-viewer"_s)
+#endif
         || LegacySchemeRegistry::schemeIsHandledBySchemeHandler(url.protocol());
 }