Implement code for Start/Finish threat details collection in WebView.

components/safe_browsing/base_blocking_page.h

Index: components/safe_browsing/base_blocking_page.h
diff --git a/components/safe_browsing/base_blocking_page.h b/components/safe_browsing/base_blocking_page.h
index d4a8c674cddb10316f7f2926e8c502dffb439925..1757d2e4f121e980b4f5da882c97ded081702f73 100644
--- a/components/safe_browsing/base_blocking_page.h
+++ b/components/safe_browsing/base_blocking_page.h
@@ -11,6 +11,7 @@
 
 #include "base/macros.h"
 #include "components/safe_browsing/base_ui_manager.h"
+#include "components/safe_browsing_db/v4_protocol_manager_util.h"
 #include "components/security_interstitials/content/security_interstitial_page.h"
 #include "components/security_interstitials/core/base_safe_browsing_error_ui.h"
 #include "components/security_interstitials/core/metrics_helper.h"
@@ -52,6 +53,9 @@ class BaseBlockingPage
   void OnDontProceed() override;
   void CommandReceived(const std::string& command) override;
 
+  // Checks the threat type to decide if we should report ThreatDetails.
+  static bool ShouldReportThreatDetails(SBThreatType threat_type);
+
  protected:
   // Don't instantiate this class directly, use ShowBlockingPage instead.
   BaseBlockingPage(