Loosen DCHECK for Omnibox Extensions

chrome/browser/autocomplete/search_provider.cc

 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/autocomplete/search_provider.h"
 
 #include <algorithm>
 #include <cmath>
 
 #include "base/base64.h"
@@ skipping 391 matching lines @@
 void SearchProvider::UpdateMatches() {
   ConvertResultsToAutocompleteMatches();
 
   // Check constraints that may be violated by suggested relevances.
   if (!matches_.empty() &&
       (default_results_.HasServerProvidedScores() ||
        keyword_results_.HasServerProvidedScores())) {
     // These blocks attempt to repair undesirable behavior by suggested
     // relevances with minimal impact, preserving other suggested relevances.
 
-    if ((providers_.GetKeywordProviderURL() != NULL) &&
+    const TemplateURL* keyword_url = providers_.GetKeywordProviderURL();
+    const bool is_extension_keyword = (keyword_url != NULL) &&
+        (keyword_url->GetType() == TemplateURL::OMNIBOX_API_EXTENSION);
+    if ((keyword_url != NULL) && !is_extension_keyword &&
         (FindTopMatch() == matches_.end())) {
-      // In keyword mode, disregard the keyword verbatim suggested relevance
-      // if necessary, so at least one match is allowed to be default.
+      // In non-extension keyword mode, disregard the keyword verbatim suggested
+      // relevance if necessary, so at least one match is allowed to be default.
+      // (In extension keyword mode this is not necessary because the extension
+      // will return a default match.)
       keyword_results_.verbatim_relevance = -1;
       ConvertResultsToAutocompleteMatches();
     }
     if (IsTopMatchSearchWithURLInput()) {
       // Disregard the suggested search and verbatim relevances if the input
       // type is URL and the top match is a highly-ranked search suggestion.
       // For example, prevent a search for "foo.com" from outranking another
       // provider's navigation for "foo.com" or "foo.com/url_from_history".
       ApplyCalculatedSuggestRelevance(&keyword_results_.suggest_results);
       ApplyCalculatedSuggestRelevance(&default_results_.suggest_results);
       default_results_.verbatim_relevance = -1;
       keyword_results_.verbatim_relevance = -1;
       ConvertResultsToAutocompleteMatches();
     }
-    if (FindTopMatch() == matches_.end()) {
-      // Guarantee that SearchProvider returns a legal default match.  (The
-      // omnibox always needs at least one legal default match, and it relies
-      // on SearchProvider to always return one.)
+    if ((FindTopMatch() == matches_.end()) && !is_extension_keyword) {

[msw, 2014/08/22 17:57:35]

optional nit: reverse conditions to match 415/416 and check the bool first.

[Mark P, 2014/08/22 18:02:18]

Done.

+      // Guarantee that SearchProvider returns a legal default match (except
+      // when in extension-based keyword mode).  The omnibox always needs at
+      // least one legal default match, and it relies on SearchProvider in
+      // combination with KeywordProvider (for extension-based keywords) to
+      // always return one.
       ApplyCalculatedRelevance();
       ConvertResultsToAutocompleteMatches();
     }
     DCHECK(!IsTopMatchSearchWithURLInput());
-    DCHECK(FindTopMatch() != matches_.end());
+    DCHECK((FindTopMatch() != matches_.end()) || is_extension_keyword);

[msw, 2014/08/22 17:57:35]

ditto nit: reverse conditions.

[Mark P, 2014/08/22 18:02:18]

Done.

   }
   UMA_HISTOGRAM_CUSTOM_COUNTS(
       "Omnibox.SearchProviderMatches", matches_.size(), 1, 6, 7);
   UpdateDone();
 }
 
 void SearchProvider::Run() {
   // Start a new request with the current input.
   suggest_results_pending_ = 0;
   time_suggest_request_sent_ = base::TimeTicks::Now();
@@ skipping 811 matching lines @@
   last_answer_seen_.query_type = match->answer_type;
 }
 
 void SearchProvider::DoAnswersQuery(const AutocompleteInput& input) {
   // If the query text starts with trimmed input, this is valid prefetch data.
   prefetch_data_ = StartsWith(last_answer_seen_.full_query_text,
                               base::CollapseWhitespace(input.text(), false),
                               false) ?
       last_answer_seen_ : AnswersQueryData();
 }