Add the ability to check the CSD Whitelist asynchronously, for PhishGuard.

components/safe_browsing_db/database_manager.h

Index: components/safe_browsing_db/database_manager.h
diff --git a/components/safe_browsing_db/database_manager.h b/components/safe_browsing_db/database_manager.h
index 01ae7caa10512703c260cdcef9ae6298f3810554..5a775623bc8f0c41a8595100083c54da23c797cd 100644
--- a/components/safe_browsing_db/database_manager.h
+++ b/components/safe_browsing_db/database_manager.h
@@ -27,6 +27,14 @@ class URLRequestContextGetter;
 
 namespace safe_browsing {
 
+// Value returned by some Check*Whitelist() calls that may or may not have an
+// immediate answer.
+enum class AsyncMatch {
+  ASYNC,     // No answer yet -- Client will get a callback
+  MATCH,     // URL matches the list.  No callback.
+  NO_MATCH,  // URL doesn't match. No callback.
+};
+
 struct V4ProtocolConfig;
 class V4GetHashProtocolManager;
 
@@ -64,6 +72,9 @@ class SafeBrowsingDatabaseManager
     virtual void OnCheckResourceUrlResult(const GURL& url,
                                           SBThreatType threat_type,
                                           const std::string& threat_hash) {}
+
+    // Called when the result of checking the CSD whitelist is known.
+    virtual void OnCheckWhitelistUrlResult(bool is_whitelisted) {}

[vakh (use Gerrit instead), 2017/05/24 16:01:17]

The comment is CSD specific but the method name is not. It'd be better to make
them consistent.

[Nathan Parker, 2017/05/31 23:40:11]

Done.

   };
 
   //
@@ -152,8 +163,15 @@ class SafeBrowsingDatabaseManager
   // side phishing detection whitelist.  Returns true if there was a match and
   // false otherwise.  To make sure we are conservative we will return true if
   // an error occurs.  This method must be called on the IO thread.
+  //
+  // DEPRECATED. ref: http://crbug.com/714300
   virtual bool MatchCsdWhitelistUrl(const GURL& url) = 0;
 
+  // Check if the |url| matches any of the full-length hashes from the client-
+  // side phishing detection whitelist. The 3-state return value indicates
+  // the result or that the Client will get a callback later with the result.
+  virtual AsyncMatch CheckCsdWhitelistUrl(const GURL& url, Client* client) = 0;

[vakh (use Gerrit instead), 2017/05/24 16:01:16]

Please move this declaration above to keep it sorted among the Check* method
declarations.

[Nathan Parker, 2017/05/31 23:40:11]

Done.

+
   // Check if |str| matches any of the full-length hashes from the download
   // whitelist.  Returns true if there was a match and false otherwise. To make
   // sure we are conservative we will return true if an error occurs.  This