InstantExtended: Bail on TemplateURLs with no espv.

chrome/browser/ui/search/search.cc

Index: chrome/browser/ui/search/search.cc
diff --git a/chrome/browser/ui/search/search.cc b/chrome/browser/ui/search/search.cc
index fae8bb0ae34d232d76e93cd1750a3f084285f47e..c58bc56642992c6a8da5f45d96c23fba53253850 100644
--- a/chrome/browser/ui/search/search.cc
+++ b/chrome/browser/ui/search/search.cc
@@ -10,8 +10,11 @@
 #include "base/string_split.h"
 #include "base/string_util.h"
 #include "chrome/browser/profiles/profile.h"
+#include "chrome/browser/search_engines/template_url_service.h"
+#include "chrome/browser/search_engines/template_url_service_factory.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/chrome_version_info.h"
+#include "googleurl/src/gurl.h"
 
 #if !defined(OS_ANDROID)
 #include "chrome/browser/themes/theme_service.h"
@@ -20,6 +23,20 @@
 
 namespace chrome {
 namespace search {
+namespace {
+// Returns whether |template_url| supports the parameter necessary to enable
+// InstantExtended.
+bool SupportsInstantExtended(const TemplateURL* template_url) {
+  if (!template_url)
+    return false;
+  const TemplateURLRef& instant_url_ref = template_url->instant_url_ref();
+  if (!instant_url_ref.IsValid())
+    return false;
+  const std::string search_url = instant_url_ref.ReplaceSearchTerms(
+      TemplateURLRef::SearchTermsArgs(string16()));
+  return template_url->HasSearchTermsReplacementKey(GURL(search_url));

[beaudoin, 2013/01/16 14:52:27]

Couldn't we assume that any TemplateURL that has a non-empty
search_terms_replacement_key support instant extended? Looking that the
instant_url_ref actually contains the search_terms_replacement key looks like a
DCHECK (since it's essentially hardcoded, coming from
prepopulated_engines.json).
Or is my assumption wrong and this "pinning" you talk about can occur on the
instant_url_ref but not in the other TemplateURL fields?

[Jered, 2013/01/16 21:27:04]

Oops sorry missed this. Your assumption was correct (though the new approach
avoids this).

+}
+}  // namespace
 
 // Configuration options for Embedded Search.
 // InstantExtended field trials are named in such a way that we can parse out
@@ -114,6 +131,15 @@ uint64 EmbeddedSearchPageVersion(Profile* profile) {
   if (!profile || profile->IsOffTheRecord())
     return 0;
 
+  // Some users may have their search provider TemplateURL pinned to an
+  // obsolete value which does not support enabling InstantExtended on the
+  // server side. Bail out of InstantExtended if we detect that.
+  const TemplateURL* template_url =
+      TemplateURLServiceFactory::GetForProfile(profile)->
+      GetDefaultSearchProvider();
+  if (!SupportsInstantExtended(template_url))
+    return 0;
+
   // Check Finch field trials.
   FieldTrialFlags flags;
   uint64 group_number = 0;
@@ -151,6 +177,7 @@ uint64 EmbeddedSearchPageVersion(Profile* profile) {
     // UI version.
     return kEmbeddedPageVersionDefault;
   }
+
   return 0;
 }