Update freetype to e1394d56752cac3bd68ab2358a8e1384ce7b9aaastaging/cm-12.0-cafstaging/cm-12.0

Integrated patches from freetype2 git repository, up to hashval
e1394d56752cac3bd68ab2358a8e1384ce7b9aaa, which is post-2.5.3.

Most recent commit message from freetype git:
  Minor documentation improvement.

Noteworthy patches included:
  Fix Savannah bug #41697, part 2.
  Fix Savannah bug #41697, part 1.

Bug: 16575323
Change-Id: I4f8f9375afd2540618b3ebf6152d77b743975dce

1 files changed, 17 insertions, 28 deletions

diff --git a/src/base/ftbitmap.c b/src/base/ftbitmap.c
index 182b1cc..6542c79 100644
--- a/src/base/ftbitmap.c
+++ b/src/base/ftbitmap.c
@@ -4,7 +4,7 @@
 /*                                                                         */
 /*    FreeType utility functions for bitmaps (body).                       */
 /*                                                                         */
-/*  Copyright 2004-2009, 2011, 2013 by                                     */
+/*  Copyright 2004-2009, 2011, 2013, 2014 by                               */
 /*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
 /*                                                                         */
 /*  This file is part of the FreeType project, and may only be used,       */
@@ -375,14 +375,11 @@
   }
 
 
-  FT_Byte
+  static FT_Byte
   ft_gray_for_premultiplied_srgb_bgra( const FT_Byte*  bgra )
   {
-    FT_Long  a = bgra[3];
-    FT_Long  b = bgra[0];
-    FT_Long  g = bgra[1];
-    FT_Long  r = bgra[2];
-    FT_Long  l;
+    FT_Byte   a = bgra[3];
+    FT_ULong  l;
 
 
     /* Short-circuit transparent color to avoid div-by-zero. */
@@ -397,38 +394,30 @@
      *
      * http://accessibility.kde.org/hsl-adjusted.php
      *
-     * We do the computation with integers only.
+     * We do the computation with integers only, applying a gamma of 2.0.
+     * The following will never overflow 32 bits; it is a scaled-up
+     * luminosity with premultiplication not yet undone. 
+     *
      */
 
-    /* Undo premultification, get the number in a 16.16 form. */
-    b = FT_MulDiv( b, 65536, a );
-    g = FT_MulDiv( g, 65536, a );
-    r = FT_MulDiv( r, 65536, a );
-    a = a * 256;
-
-    /* Apply gamma of 2.0 instead of 2.2. */
-    b = FT_MulFix( b, b );
-    g = FT_MulFix( g, g );
-    r = FT_MulFix( r, r );
-
-    /* Apply coefficients. */
-    b = FT_MulFix( b,  4731 /* 0.0722 * 65536 */ );
-    g = FT_MulFix( g, 46871 /* 0.7152 * 65536 */ );
-    r = FT_MulFix( r, 13933 /* 0.2126 * 65536 */ );
-
-    l = r + g + b;
+    l =  4731UL /* 0.0722 * 65536 */ * bgra[0] * bgra[0] +
+        46871UL /* 0.7152 * 65536 */ * bgra[1] * bgra[1] +
+        13933UL /* 0.2126 * 65536 */ * bgra[2] * bgra[2];
 
     /*
-     * Final transparency can be determined this way:
+     * Final transparency can be determined as follows.
      *
      * - If alpha is zero, we want 0.
      * - If alpha is zero and luminosity is zero, we want 255.
      * - If alpha is zero and luminosity is one, we want 0.
      *
-     * So the formula is a * (1 - l).
+     * So the formula is a * (1 - l) = a - l * a.
+     *
+     * In the actual code, we undo premultiplication and scale down again.
+     *
      */
 
-    return (FT_Byte)( FT_MulFix( 65535 - l, a ) >> 8 );
+    return a - (FT_Byte)( ( l / a ) >> 16 );
   }