Update to Harfbuzz 2.6.4

Quite a big change since it has been several years since
the last update. This drops the Harfbuzz source on top
of the existing code in Qt, and does the following
additional changes:

1. Deletes old source files that have been removed upstream
(everything named foo-private.hh is now renamed to just
foo.hh for instance).

2. Added a header guard to config.h because it may be
double-included.

3. Implement a memory barrier needed by hb-atomic.hh.

4. Changed the signature of hb_atomic_int_impl_add()
to take a pointer to match new upstream.

5. Updated .pro file to include new files and removed
old.

6. Updated qt_attribution.json

7. No longer disable deprecated APIs since
hb_ot_tags_from_script() is now deprecated and is used
from Qt code.

8. Updated and applied the patch in patches/ for CoreText.

9. Updated tst_qtextscriptengine::thaiWithZWJ() according to
changes in Harfbuzz and disabled it for system-harfbuzz,
since this may be an older version of harfbuzz depending on
the system.

Fixes: QTBUG-79606
Change-Id: I3f057a43ff44ee416628b75ef12fb1a221f31910
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Lars Knoll <lars.knoll@qt.io>

1 files changed, 22 insertions, 1 deletions

diff --git a/src/3rdparty/harfbuzz-ng/src/hb-ot-math.h b/src/3rdparty/harfbuzz-ng/src/hb-ot-math.h
index 521a5ca037..ad864a762d 100644
--- a/src/3rdparty/harfbuzz-ng/src/hb-ot-math.h
+++ b/src/3rdparty/harfbuzz-ng/src/hb-ot-math.h
@@ -50,6 +50,9 @@ HB_BEGIN_DECLS
 /**
  * hb_ot_math_constant_t:
  *
+ * The 'MATH' table constants specified at
+ * https://docs.microsoft.com/en-us/typography/opentype/spec/math
+ *
  * Since: 1.3.3
  */
 typedef enum {
@@ -114,6 +117,9 @@ typedef enum {
 /**
  * hb_ot_math_kern_t:
  *
+ * The math kerning-table types defined for the four corners
+ * of a glyph.
+ *
  * Since: 1.3.3
  */
 typedef enum {
@@ -125,6 +131,10 @@ typedef enum {
 
 /**
  * hb_ot_math_glyph_variant_t:
+ * @glyph: The glyph index of the variant
+ * @advance: The advance width of the variant
+ *
+ * Data type to hold math-variant information for a glyph.
  *
  * Since: 1.3.3
  */
@@ -136,14 +146,25 @@ typedef struct hb_ot_math_glyph_variant_t {
 /**
  * hb_ot_math_glyph_part_flags_t:
  *
+ * Flags for math glyph parts.
+ *
  * Since: 1.3.3
  */
 typedef enum { /*< flags >*/
-  HB_MATH_GLYPH_PART_FLAG_EXTENDER	= 0x00000001u  /* Extender glyph */
+  HB_OT_MATH_GLYPH_PART_FLAG_EXTENDER	= 0x00000001u  /* Extender glyph */
 } hb_ot_math_glyph_part_flags_t;
 
 /**
  * hb_ot_math_glyph_part_t:
+ * @glyph: The glyph index of the variant part
+ * @start_connector_length: The length of the connector on the starting side of the variant part
+ * @end_connector_length: The length of the connector on the ending side of the variant part
+ * @full_advance: The total advance of the part
+ * @flags: #hb_ot_math_glyph_part_flags_t flags for the part
+ * 
+ * Data type to hold information for a "part" component of a math-variant glyph.
+ * Large variants for stretchable math glyphs (such as parentheses) can be constructed
+ * on the fly from parts.
  *
  * Since: 1.3.3
  */