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

content/browser/web_contents/navigation_entry_impl_unittest.cc

Index: content/browser/web_contents/navigation_entry_impl_unittest.cc
diff --git a/content/browser/web_contents/navigation_entry_impl_unittest.cc b/content/browser/web_contents/navigation_entry_impl_unittest.cc
index 0e8fa33f6cbcb6e7ab0aca93b88ffbd21c9ad68e..00857ed329fbd123a859e34e9bce92a4a500541f 100644
--- a/content/browser/web_contents/navigation_entry_impl_unittest.cc
+++ b/content/browser/web_contents/navigation_entry_impl_unittest.cc
@@ -217,4 +217,25 @@ TEST_F(NavigationEntryTest, NavigationEntryTimestamps) {
   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