Passing BackgroundColorSpan and UnderlineSpan from Clank to Blink.

ui/base/ime/composition_underline.h

Index: ui/base/ime/composition_underline.h
diff --git a/ui/base/ime/composition_underline.h b/ui/base/ime/composition_underline.h
index c8d09d8416336eb0b86ece88b53af062a80efb04..cfc2d455bb65edcec7f87ecb556704945791dba6 100644
--- a/ui/base/ime/composition_underline.h
+++ b/ui/base/ime/composition_underline.h
@@ -18,19 +18,30 @@ struct CompositionUnderline {
     : start_offset(0),
       end_offset(0),
       color(0),
-      thick(false) {}
+      thick(false),
+      background_color(0) {}
 
+  // TODO(huangs): remove this constructor.
   CompositionUnderline(unsigned s, unsigned e, SkColor c, bool t)
     : start_offset(s),
       end_offset(e),
       color(c),
-      thick(t) {}
+      thick(t),
+      background_color(0) {}
+
+  CompositionUnderline(unsigned s, unsigned e, SkColor c, bool t, SkColor bc)
+    : start_offset(s),
+      end_offset(e),
+      color(c),
+      thick(t),
+      background_color(bc) {}
 
   bool operator==(const CompositionUnderline& rhs) const {
     return (this->start_offset == rhs.start_offset) &&
         (this->end_offset == rhs.end_offset) &&
         (this->color == rhs.color) &&
-        (this->thick == rhs.thick);
+        (this->thick == rhs.thick) &&
+        (this->background_color == rhs.background_color);
   }
 
   bool operator!=(const CompositionUnderline& rhs) const {
@@ -43,6 +54,7 @@ struct CompositionUnderline {
   unsigned end_offset;
   SkColor color;
   bool thick;
+  SkColor background_color;
 };
 
 typedef std::vector<CompositionUnderline> CompositionUnderlines;