Support for Sgaw and W Pwo Karen languages in the Myanmar validator.

1. Added 0x102c and 0x1062 in the tone mark section, in Karen these can
be tones too.

2. Added the optional 0x103a, 0x1037, and 0x1038 after the tones. Asat
is part of the Sgaw tone mark and dot below and visarga are used as
nasal marks following the Pwo tones.

src/training/unicharset/validate_myanmar.cpp

@@ -140,13 +140,21 @@ bool ValidateMyanmar::ConsumeOptionalSignsIfPresent() {
   }
   // Tone mark extensions.
   ch = codes_[codes_used_].second;
-  if (ch == 0x1038 || ch == kMyanmarAsat || ch == 0x1063 || ch == 0x1064 ||
+  if (ch == 0x102c || ch == 0x1038 || ch == kMyanmarAsat || (0x1062 <= ch && ch <= 0x1064) ||
       (0x1069 <= ch && ch <= 0x106d) || (0x1087 <= ch && ch <= 0x108d) || ch == 0x108f ||
       ch == 0x109a || ch == 0x109b || (0xaa7b <= ch && ch <= 0xaa7d)) {
     if (UseMultiCode(1)) {
       return true;
     }
   }
+  // Sgaw tones 0x1062, 0x1063 must be followed by asat.
+  // W Pwo tones 0x1069, 0x106a, and 0x106b may be followed by dot below or visarga (nasal).
+  ch = codes_[codes_used_].second; 
+  if (ch == 0x103a || ch == 0x1037 || ch == 0x1038) {
+    if (UseMultiCode(1)) {
+      return true;
+    }
+  }
   return false;
 }