[Search] Store and recall search terms using NavigationEntry to improve search term extraction

content/browser/web_contents/navigation_entry_impl_unittest.cc

 // Copyright (c) 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 "base/string16.h"
 #include "base/string_util.h"
 #include "base/time.h"
 #include "base/utf_string_conversions.h"
 #include "content/browser/site_instance_impl.h"
 #include "content/browser/web_contents/navigation_entry_impl.h"
@@ skipping 199 matching lines @@
 }
 
 // Test timestamps.
 TEST_F(NavigationEntryTest, NavigationEntryTimestamps) {
   EXPECT_EQ(base::Time(), entry1_->GetTimestamp());
   const base::Time now = base::Time::Now();
   entry1_->SetTimestamp(now);
   EXPECT_EQ(now, entry1_->GetTimestamp());
 }
 
+// Test extra data stored in the navigation entry.
+TEST_F(NavigationEntryTest, NavigationEntryExtraData) {
+  string16 test_data = ASCIIToUTF16("my search terms");
+  string16 output;
+  entry1_->SetExtraData("search_terms", test_data);
+
+  EXPECT_FALSE(entry1_->GetExtraData("non_existent_key", &output));
+  EXPECT_EQ(ASCIIToUTF16(""), output);
+  EXPECT_TRUE(entry1_->GetExtraData("search_terms", &output));
+  EXPECT_EQ(test_data, output);
+  // Data is cleared.
+  entry1_->ClearExtraData("search_terms");
+  // Content in |output| is not modified if data is not present at the key.
+  EXPECT_FALSE(entry1_->GetExtraData("search_terms", &output));
+  EXPECT_EQ(test_data, output);
+  // Using an empty string shows that the data is not present in the map.
+  string16 output2;
+  EXPECT_FALSE(entry1_->GetExtraData("search_terms", &output2));
+  EXPECT_EQ(ASCIIToUTF16(""), output2);
+}
+
 }  // namespace content