Code:  TemplateURLRef::SearchTermsArgs::ContextualSearchParams::ContextualSearchParams(
     int version,
     const std::string& selection,
     const std::string& base_page_url,
    int now_on_tap_version)
     : version(version),
       start(base::string16::npos),
       end(base::string16::npos),
       selection(selection),
       base_page_url(base_page_url),
      now_on_tap_version(now_on_tap_version) {}

Commit Message: [Contextual Search] Change "Now on Tap" to "Contextual Cards"

BUG=644934

Review-Url: https://codereview.chromium.org/2361163003
Cr-Commit-Position: refs/heads/master@{#420899}
CWE ID: 
 TemplateURLRef::SearchTermsArgs::ContextualSearchParams::ContextualSearchParams(
     int version,
     const std::string& selection,
     const std::string& base_page_url,
    int contextual_cards_version)
     : version(version),
       start(base::string16::npos),
       end(base::string16::npos),
       selection(selection),
       base_page_url(base_page_url),
