Add support for persisting CompositionUnderlines in InputMethodController

third_party/WebKit/public/web/WebCompositionUnderline.h

Index: third_party/WebKit/public/web/WebCompositionUnderline.h
diff --git a/third_party/WebKit/public/web/WebCompositionUnderline.h b/third_party/WebKit/public/web/WebCompositionUnderline.h
index 3252ec1d1a3cccaf5b43e83d1d6903c856dc9019..970596cb37b5660dc353751f1c56f6c9bc2102d2 100644
--- a/third_party/WebKit/public/web/WebCompositionUnderline.h
+++ b/third_party/WebKit/public/web/WebCompositionUnderline.h
@@ -43,14 +43,21 @@ struct WebCompositionUnderline {
         endOffset(0),
         color(0),
         thick(false),
-        backgroundColor(0) {}
+        backgroundColor(0),
+        persist(false) {}
 
   WebCompositionUnderline(unsigned s,
                           unsigned e,
                           WebColor c,
                           bool t,
-                          WebColor bc)
-      : startOffset(s), endOffset(e), color(c), thick(t), backgroundColor(bc) {}
+                          WebColor bc,
+                          bool p)
+      : startOffset(s),
+        endOffset(e),
+        color(c),
+        thick(t),
+        backgroundColor(bc),
+        persist(p) {}
 
   bool operator<(const WebCompositionUnderline& other) const {
     return startOffset != other.startOffset ? startOffset < other.startOffset
@@ -64,6 +71,7 @@ struct WebCompositionUnderline {
   WebColor color;
   bool thick;
   WebColor backgroundColor;
+  bool persist;
 };
 
 }  // namespace blink