Refactor safe-browsing build-config definitions.

chrome/browser/safe_browsing/safe_browsing_tab_observer.h

Index: chrome/browser/safe_browsing/safe_browsing_tab_observer.h
diff --git a/chrome/browser/safe_browsing/safe_browsing_tab_observer.h b/chrome/browser/safe_browsing/safe_browsing_tab_observer.h
index c7ddab6ae1c8ba0f01f47c722f1fc6b98705fb28..8a064949bc261e6d49196c68ad460f02c138f14b 100644
--- a/chrome/browser/safe_browsing/safe_browsing_tab_observer.h
+++ b/chrome/browser/safe_browsing/safe_browsing_tab_observer.h
@@ -23,13 +23,8 @@ class SafeBrowsingTabObserver
  public:
   virtual ~SafeBrowsingTabObserver();
 
-  ClientSideDetectionHost* detection_host() {
-    return safebrowsing_detection_host_.get();
-  }
-
-  const ClientSideDetectionHost* detection_host() const {
-    return safebrowsing_detection_host_.get();
-  }
+  // Forward to detection host, if safe-browsing is enabled.
+  bool DidPageReceiveSafeBrowsingMatch() const;
 
  private:
   explicit SafeBrowsingTabObserver(content::WebContents* web_contents);