Add a class to parse answer json.

components/omnibox/autocomplete_match.h

Index: components/omnibox/autocomplete_match.h
diff --git a/components/omnibox/autocomplete_match.h b/components/omnibox/autocomplete_match.h
index cb1f6e4258f80a00e0c0b861ca15e0ecfdeef475..9e5da3ca4507ae006c363fb2c259baf6f8d24355 100644
--- a/components/omnibox/autocomplete_match.h
+++ b/components/omnibox/autocomplete_match.h
@@ -11,6 +11,7 @@
 
 #include "base/memory/scoped_ptr.h"
 #include "components/omnibox/autocomplete_match_type.h"
+#include "components/omnibox/suggestion_answer.h"
 #include "components/search_engines/template_url.h"
 #include "ui/base/page_transition_types.h"
 #include "url/gurl.h"
@@ -317,9 +318,12 @@ struct AutocompleteMatch {
   base::string16 description;
   ACMatchClassifications description_class;
 
+  // TODO(jdonnelly): Remove the first two properties once the downstream
+  // clients are using the SuggestionAnswer.

[Peter Kasting, 2014/10/24 22:38:09]

Does this just mean chrome/ code?  Is it not possible to change this all at
once, or were just trying to keep the change smaller and more reviewable? 
(Which I'm fine with)

[Justin Donnelly, 2014/10/27 21:41:15]

Yeah, I'd probably do it just to keep the change size manageable but the driving
reason is that Clank (and maybe Bling?) rolls the main repository to their build
periodically, so the changes have to be staged.

   // A rich-format version of the display for the dropdown.
   base::string16 answer_contents;
   base::string16 answer_type;
+  SuggestionAnswer answer;
 
   // The transition type to use when the user opens this match.  By default
   // this is TYPED.  Providers whose matches do not look like URLs should set