Do not break after ZWJ if the trailing character is Emoji.

third_party/WebKit/Source/platform/text/Character.h

Index: third_party/WebKit/Source/platform/text/Character.h
diff --git a/third_party/WebKit/Source/platform/text/Character.h b/third_party/WebKit/Source/platform/text/Character.h
index 2f64ac543ad5e6217906e55d4da5c76e116f56a0..1b8a1a55e5f148d70da1941e55169a8ea08c30eb 100644
--- a/third_party/WebKit/Source/platform/text/Character.h
+++ b/third_party/WebKit/Source/platform/text/Character.h
@@ -112,6 +112,7 @@ public:
         return u_hasBinaryProperty(c, UCHAR_GRAPHEME_EXTEND);
     }
 
+    static bool isEmoji(UChar32);

[tkent, 2016/04/20 01:56:28]

Need a comment.  Difference between isEmoji and following functions looks
unclear to me.

[Seigo Nonaka, 2016/04/20 07:39:41]

Done.

     // Default presentation style according to:
     // http://www.unicode.org/reports/tr51/#Presentation_Style
     static bool isEmojiTextDefault(UChar32);