Improve variation comment for iOS.

CTFontCopyVariationAxes returns nullptr for fonts which began life with
CGFontCreateWithDataProvider on macOS 10.10 and earlier and iOS 9 and
earlier. The issue was fixed in maxOS 10.11 and iOS 10. Improve the
existing comments to make this clear.

Change-Id: I0de1734e266d30aab7d38d0dd752f66259f677d9
Reviewed-on: https://skia-review.googlesource.com/14278
Reviewed-by: Ben Wagner <bungeman@google.com>
Commit-Queue: Ben Wagner <bungeman@google.com>

diff --git a/src/ports/SkFontHost_mac.cpp b/src/ports/SkFontHost_mac.cpp
index 4c5added4cda194d08b1aa5f51b01aa02252bf95..b525ed597f231ba4b88f3865a7ea5ec83af10d59 100644 (file)
--- a/src/ports/SkFontHost_mac.cpp
+++ b/src/ports/SkFontHost_mac.cpp
@@ -1848,8 +1848,8 @@ int SkTypeface_Mac::onGetVariationDesignPosition(
 {
     // The CGFont variation data does not contain the tag.
 
-    // This call always returns nullptr on 10.10 and under for CGFontCreateWithDataProvider fonts.
-    // When this happens, there is no API to provide the tag.
+    // CTFontCopyVariationAxes returns nullptr for CGFontCreateWithDataProvider fonts with
+    // macOS 10.10 and iOS 9 or earlier. When this happens, there is no API to provide the tag.
     UniqueCFRef<CFArrayRef> ctAxes(CTFontCopyVariationAxes(fFontRef.get()));
     if (!ctAxes) {
         return -1;
@@ -2425,8 +2425,8 @@ protected:
         // CTFont variation dictionary runs into bugs. So use the CTFont variation data
         // to match names to tags to create the appropriate CGFont.
         UniqueCFRef<CTFontRef> ct(CTFontCreateWithGraphicsFont(cg, 0, nullptr, nullptr));
-        // This call always returns nullptr on 10.10 and under.
-        // When this happens, there is no API to provide the tag.
+        // CTFontCopyVariationAxes returns nullptr for CGFontCreateWithDataProvider fonts with
+        // macOS 10.10 and iOS 9 or earlier. When this happens, there is no API to provide the tag.
         UniqueCFRef<CFArrayRef> ctAxes(CTFontCopyVariationAxes(ct.get()));
         if (!ctAxes) {
             return nullptr;