LyX: add a patch to Qt4 variant for broken QRawFont

aqua/LyX/Portfile

@@ -93,6 +93,12 @@ variant qt4 conflicts qt5 description {Use Qt4} {
                         --with-version-suffix=-${branch} \
                         --with-qt-dir=${prefix}/libexec/qt4 \
                         --disable-qt5
+
+    # QRawFont is supposed to work, but does not:
+    # GuiFontMetrics.cpp:127:9: error: 'QRawFont' was not declared in this scope; did you mean 'QFont'?
+    # Anyway, it seems to have issues in Qt4:
+    # https://stackoverflow.com/questions/12597595/qrawfontfromfont-not-working-correctly
+    patchfiles-append   patch-GuiFontMetrics.cpp.diff
 }
 
 variant qt5 conflicts qt4 description {Use Qt5} {
@@ -117,6 +123,7 @@ variant qt5 conflicts qt4 description {Use Qt5} {
 
 # error: '-fobjc-exceptions' is required to enable Objective-C exception syntax
 if {[string match *gcc* ${configure.compiler}]} {
+    # This must be set in pre-configure:
     pre-configure {
         configure.objcflags-append \
                         -fobjc-exceptions

aqua/LyX/files/patch-GuiFontMetrics.cpp.diff

@@ -0,0 +1,19 @@
+--- src/frontends/qt4/GuiFontMetrics.cpp
++++ src/frontends/qt4/GuiFontMetrics.cpp	2024-08-30 20:05:29.000000000 +0800
+@@ -122,6 +122,8 @@
+ 	  breakat_cache_(cache_metrics_breakat_size),
+ 	  qtextlayout_cache_(cache_metrics_qtextlayout_size)
+ {
++// For w/e reason QRawFont is not recognized, despite its header being included.
++#ifndef __APPLE__
+ 	// Determine italic slope
+ 	double const defaultSlope = tan(qDegreesToRadians(19.0));
+ 	QRawFont raw = QRawFont::fromFont(font);
+@@ -137,6 +139,7 @@
+ 		slope_ = -tan(qDegreesToRadians(angle));
+ 		LYXERR(Debug::FONT, "Italic slope: " << slope_);
+ 	}
++#endif
+ }
+ 
+