Make harfbuzz build for iOS

Change-Id: Ifc28ac50a453eef8aa2f31d02ac513db0222eb4e

external/harfbuzz/UnpackedTarball_harfbuzz.mk

@@ -26,4 +26,8 @@ $(eval $(call gb_UnpackedTarball_add_patches,harfbuzz, \
 ))
 endif
 
+$(eval $(call gb_UnpackedTarball_add_patches,harfbuzz, \
+    external/harfbuzz/harfbuzz-ios.patch \
+))
+
 # vim: set noet sw=4 ts=4:

external/harfbuzz/harfbuzz-ios.patch

+--- src/hb-coretext.cc
++++ src/hb-coretext.cc
+@@ -167,7 +167,7 @@
+   if (CFStringHasPrefix (cg_postscript_name, CFSTR (".SFNSText")) ||
+       CFStringHasPrefix (cg_postscript_name, CFSTR (".SFNSDisplay")))
+   {
+-#if MAC_OS_X_VERSION_MIN_REQUIRED < 1080
++#if !defined(__IPHONE_OS_VERSION_MIN_REQUIRED) && (MAC_OS_X_VERSION_MIN_REQUIRED < 1080)
+ # define kCTFontUIFontSystem kCTFontSystemFontType
+ # define kCTFontUIFontEmphasizedSystem kCTFontEmphasizedSystemFontType
+ #endif
+@@ -217,7 +217,7 @@
+   }
+ 
+   CFURLRef original_url = nullptr;
+-#if MAC_OS_X_VERSION_MIN_REQUIRED < 1060
++#if !defined(__IPHONE_OS_VERSION_MIN_REQUIRED) && (MAC_OS_X_VERSION_MIN_REQUIRED < 1060)
+   ATSFontRef atsFont;
+   FSRef fsref;
+   OSStatus status;
+@@ -240,7 +240,7 @@
+        * process in Blink. This can be detected by the new file URL location
+        * that the newly found font points to. */
+       CFURLRef new_url = nullptr;
+-#if MAC_OS_X_VERSION_MIN_REQUIRED < 1060
++#if !defined(__IPHONE_OS_VERSION_MIN_REQUIRED) && (MAC_OS_X_VERSION_MIN_REQUIRED < 1060)
+       atsFont = CTFontGetPlatformFont (new_ct_font, NULL);
+       status = ATSFontGetFileReference (atsFont, &fsref);
+       if (status == noErr)