Remove |kAltInstantURLPath| from search.cc and retain the default Instant...

Remove |kAltInstantURLPath| from search.cc and retain the default Instant search base url path when the |kUseAltInstantURL| flag is enabled. 

BUG=382694
TEST=Run chrome with the following field trial flag and observe the Instant search base page url.
     --force-fieldtrials="EmbeddedSearch/Group1 use_alternate_instant_url:1 /"

Review URL: https://codereview.chromium.org/453573002

Cr-Commit-Position: refs/heads/master@{#289046}
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@289046 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/search/search.cc

@@ -61,7 +61,6 @@ const char kReuseInstantSearchBasePage[] = "reuse_instant_search_base_page";
 // Controls whether to use the alternate Instant search base URL. This allows
 // experimentation of Instant search.
 const char kUseAltInstantURL[] = "use_alternate_instant_url";
-const char kAltInstantURLPath[] = "search";
 const char kAltInstantURLQueryParams[] = "&qbp=1";
 
 const char kDisplaySearchButtonFlagName[] = "display_search_button";
@@ -494,8 +493,6 @@ GURL GetInstantURL(Profile* profile, bool force_instant_results) {
 
   if (ShouldUseAltInstantURL()) {
     GURL::Replacements replacements;
-    const std::string path(kAltInstantURLPath);
-    replacements.SetPathStr(path);
     const std::string query(
         instant_url.query() + std::string(kAltInstantURLQueryParams));
     replacements.SetQueryStr(query);

chrome/browser/search/search_unittest.cc

@@ -474,7 +474,7 @@ TEST_F(SearchTest, GetInstantURL) {
   profile()->GetPrefs()->SetBoolean(prefs::kSearchSuggestEnabled, true);
   ASSERT_TRUE(base::FieldTrialList::CreateFieldTrial(
       "EmbeddedSearch", "Group1 espv:8 use_alternate_instant_url:1"));
-  EXPECT_EQ(GURL("https://foo.com/search?foo=foo&qbp=1#foo=foo&strk"),
+  EXPECT_EQ(GURL("https://foo.com/instant?foo=foo&qbp=1#foo=foo&strk"),
             GetInstantURL(profile(), false));
 }