Partially componentize //chrome/browser/search/search.{h,cc}

components/search/search.h

 // Copyright 2014 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.
 
 #ifndef COMPONENTS_SEARCH_SEARCH_H_
 #define COMPONENTS_SEARCH_SEARCH_H_
 
 #include <string>
 #include <utility>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/strings/string16.h"
 #include "base/strings/string_split.h"
 
-namespace chrome {
+class GURL;
+class TemplateURL;
+
+namespace search {
+
+// Use this value for "start margin" to prevent the "es_sm" parameter from
+// being used.
+extern const int kDisableStartMargin;
 
 // Returns whether the Instant Extended API is enabled.
 bool IsInstantExtendedAPIEnabled();
 
 // Returns the value to pass to the &espv CGI parameter when loading the
 // embedded search page from the user's default search provider. Returns 0 if
 // the Instant Extended API is not enabled.
 uint64 EmbeddedSearchPageVersion();
 
 // Type for a collection of experiment configuration parameters.
@@ skipping 21 matching lines @@
 uint64 GetUInt64ValueForFlagWithDefault(const std::string& flag,
                                         uint64 default_value,
                                         const FieldTrialFlags& flags);
 
 // Given a FieldTrialFlags object, returns the bool value of the provided flag.
 // Exposed for testing only.
 bool GetBoolValueForFlagWithDefault(const std::string& flag,
                                     bool default_value,
                                     const FieldTrialFlags& flags);
 
-}  // namespace chrome
+// Returns a string indicating whether InstantExtended is enabled, suitable
+// for adding as a query string param to the homepage or search requests.
+// Returns an empty string otherwise.
+//
+// |for_search| should be set to true for search requests, in which case this
+// returns a non-empty string only if query extraction is enabled.
+std::string InstantExtendedEnabledParam(bool for_search);
+
+// Returns a string that will cause the search results page to update
+// incrementally. Currently, Instant Extended passes a different param to
+// search results pages that also has this effect, so by default this function
+// returns the empty string when Instant Extended is enabled. However, when
+// doing instant search result prerendering, we still need to pass this param,
+// as Instant Extended does not cause incremental updates by default for the
+// prerender page. Callers should set |for_prerender| in this case to force
+// the returned string to be non-empty.
+std::string ForceInstantResultsParam(bool for_prerender);
+
+// Returns whether query extraction is enabled.
+bool IsQueryExtractionEnabled();
+
+// Returns true if 'prefetch_results' flag is set to true in field trials to
+// prefetch high-confidence search suggestions.
+bool ShouldPrefetchSearchResults();
+
+// Returns true if 'reuse_instant_search_base_page' flag is set to true in field
+// trials to reuse the prerendered page to commit any search query.
+bool ShouldReuseInstantSearchBasePage();
+
+// Returns true if 'allow_prefetch_non_default_match' flag is enabled in field
+// trials to allow prefetching the suggestion marked to be prefetched by the
+// suggest server even if it is not the default match.
+bool ShouldAllowPrefetchNonDefaultMatch();
+
+// |url| should either have a secure scheme or have a non-HTTPS base URL that
+// the user specified using --google-base-url. (This allows testers to use
+// --google-base-url to point at non-HTTPS servers, which eases testing.)
+bool IsSuitableURLForInstant(const GURL& url, const TemplateURL* template_url);

[Jered, 2015/07/31 15:38:45]

This function prototype wasn't exposed previously. Is there a caller outside
search.cc, now?

[sdefresne, 2015/07/31 17:09:30]

There were three call sites in chrome/browser/search/search.cc, but two of them
in function that cannot be moved into the component "bool IsInstantURL(const
GURL& url, Profile* profile)" and "bool IsQueryExtractionAllowedForURL(Profile*
profile, const GURL& url)" as they depends on Profile (which cannot be used in a
component as it is defined in src/chrome/browser).

If you do not want this to be public, I can put it in a search_internal.h file
and add a comment saying that the content of the file should only be used by
components/search and chrome/browser/search (maybe with a
-components/search/search_internal.h DEPS in //chrome/browser with the
corresponding +components/search/search_internal.h in //chrome/browser/search).

I'm exporting it to be usable for iOS implementation of "bool
IsQueryExtractionAllowedForURL(ios::ChromeBrowserState* browser_state, const
GURL& url)" and I'd prefer not to have to duplicate it.

WDYT?

[Jered, 2015/07/31 19:50:11]

It's fine here. Thanks for explaining the rationale.

+
+// -----------------------------------------------------
+// The following APIs are exposed for use in tests only.
+// -----------------------------------------------------
+
+// Forces query in the omnibox to be on for tests.
+void EnableQueryExtractionForTesting();
+
+}  // namespace search
 
 #endif  // COMPONENTS_SEARCH_SEARCH_H_