Patch for ICU 7.4
See https://hg.mozilla.org/try/rev/d5f3b0c4f08a426ce00a153c04e177eecb6820e2
See https://bugs.gentoo.org/917599

diff --git a/intl/lwbrk/LineBreaker.cpp b/intl/lwbrk/LineBreaker.cpp
--- a/intl/lwbrk/LineBreaker.cpp
+++ b/intl/lwbrk/LineBreaker.cpp
@@ -443,17 +443,23 @@ static int8_t GetClass(uint32_t u, LineB
       /* JT = 34,                           [JT] */ CLASS_CHARACTER,
       /* JV = 35,                           [JV] */ CLASS_CHARACTER,
       /* CLOSE_PARENTHESIS = 36,            [CP] */ CLASS_CLOSE_LIKE_CHARACTER,
       /* CONDITIONAL_JAPANESE_STARTER = 37, [CJ] */ CLASS_CLOSE,
       /* HEBREW_LETTER = 38,                [HL] */ CLASS_CHARACTER,
       /* REGIONAL_INDICATOR = 39,           [RI] */ CLASS_CHARACTER,
       /* E_BASE = 40,                       [EB] */ CLASS_BREAKABLE,
       /* E_MODIFIER = 41,                   [EM] */ CLASS_CHARACTER,
-      /* ZWJ = 42,                          [ZWJ]*/ CLASS_CHARACTER};
+      /* ZWJ = 42,                          [ZWJ]*/ CLASS_CHARACTER,
+      /* AKSARA = 43,                       [AK] */ CLASS_CHARACTER,
+      /* AKSARA_PREBASE = 44,               [AP] */ CLASS_CHARACTER,
+      /* AKSARA_START = 45,                 [AS] */ CLASS_CHARACTER,
+      /* VIRAMA_FINAL = 46,                 [VF] */ CLASS_CHARACTER,
+      /* VIRAMA = 47,                       [VI] */ CLASS_CHARACTER,
+  };
 
   static_assert(U_LB_COUNT == mozilla::ArrayLength(sUnicodeLineBreakToClass),
                 "Gecko vs ICU LineBreak class mismatch");
 
   auto cls = GetLineBreakClass(u);
   MOZ_ASSERT(cls < mozilla::ArrayLength(sUnicodeLineBreakToClass));
 
   // Overrides based on rules for the different line-break values given in