Add a class to parse answer json.

components/omnibox/autocomplete_match.cc

Index: components/omnibox/autocomplete_match.cc
diff --git a/components/omnibox/autocomplete_match.cc b/components/omnibox/autocomplete_match.cc
index 558ed93c417838a47d571751bb9febce2e7b83d4..1340e27e05936c29b72ee3b9101e545fd84d6a22 100644
--- a/components/omnibox/autocomplete_match.cc
+++ b/components/omnibox/autocomplete_match.cc
@@ -12,6 +12,7 @@
 #include "base/strings/utf_string_conversions.h"
 #include "base/time/time.h"
 #include "components/omnibox/autocomplete_provider.h"
+#include "components/omnibox/suggestion_answer.h"
 #include "components/search_engines/template_url.h"
 #include "components/search_engines/template_url_service.h"
 #include "grit/components_scaled_resources.h"
@@ -79,6 +80,7 @@ AutocompleteMatch::AutocompleteMatch(const AutocompleteMatch& match)
       description_class(match.description_class),
       answer_contents(match.answer_contents),
       answer_type(match.answer_type),
+      answer(match.answer.get() ? new SuggestionAnswer(*match.answer) : NULL),

[groby-ooo-7-16, 2014/10/21 00:35:54]

UGH. I forgot that AutocompleteMatch can be copy-constructed. That probably
means we should refcount it, if we really care about savings. (Which opens
another can of worms...)

[Justin Donnelly, 2014/10/21 21:43:54]

Yes, I agree that option #2 is probably the right answer (always having a value
for the answer object).  It seems undesirable to have the overhead but the
reality is we're talking about dozens of suggestion and match objects, not
thousands.

I've made the change to eliminate the scoped_ptrs and the new copy constructor
and assignment operator.  The code is much nicer now.  Let me know what you
think.

       transition(match.transition),
       is_history_what_you_typed_match(match.is_history_what_you_typed_match),
       type(match.type),
@@ -116,6 +118,7 @@ AutocompleteMatch& AutocompleteMatch::operator=(
   description_class = match.description_class;
   answer_contents = match.answer_contents;
   answer_type = match.answer_type;
+  answer.reset(match.answer.get() ? new SuggestionAnswer(*match.answer) : NULL);
   transition = match.transition;
   is_history_what_you_typed_match = match.is_history_what_you_typed_match;
   type = match.type;