Split to SafeBrowsingDatabaseManager into Local* and Remote*.

chrome/browser/safe_browsing/remote_database_manager.cc

+// Copyright (c) 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/safe_browsing/remote_database_manager.h"
+
+#include <vector>
+
+#include "chrome/browser/safe_browsing/android_safe_browsing_api_handler.h"
+#include "content/public/browser/browser_thread.h"
+
+using content::BrowserThread;
+
+// TODO(nparker): Add tests for this class once implemented.
+RemoteSafeBrowsingDatabaseManager::RemoteSafeBrowsingDatabaseManager()
+    : enabled_(false) {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+  // TODO(nparker): Implement the initialization glue.
+  // Check flag to see if this is enabled.
+  // Ask AndroidSafeBrowsingAPIHandler if Java API is correct version.
+}
+
+RemoteSafeBrowsingDatabaseManager::~RemoteSafeBrowsingDatabaseManager() {
+  DCHECK(!enabled_);
+}
+
+bool RemoteSafeBrowsingDatabaseManager::CanCheckUrl(const GURL& url) const {
+  return url.SchemeIs(url::kHttpsScheme) || url.SchemeIs(url::kHttpScheme) ||
+         url.SchemeIs(url::kFtpScheme);
+}
+
+bool RemoteSafeBrowsingDatabaseManager::download_protection_enabled()
+    const {
+  return false;
+}
+
+bool RemoteSafeBrowsingDatabaseManager::CheckDownloadUrl(
+    const std::vector<GURL>& url_chain,
+    Client* client) {
+  NOTREACHED();
+  return true;
+}
+
+bool RemoteSafeBrowsingDatabaseManager::CheckExtensionIDs(
+    const std::set<std::string>& extension_ids,
+    Client* client) {
+  NOTREACHED();
+  return true;
+}
+
+bool RemoteSafeBrowsingDatabaseManager::MatchMalwareIP(
+    const std::string& ip_address) {
+  NOTREACHED();
+  return false;
+}
+
+bool RemoteSafeBrowsingDatabaseManager::MatchCsdWhitelistUrl(const GURL& url) {
+  NOTREACHED();
+  return true;
+}
+
+bool RemoteSafeBrowsingDatabaseManager::MatchDownloadWhitelistUrl(
+    const GURL& url) {
+  NOTREACHED();
+  return true;
+}
+
+bool RemoteSafeBrowsingDatabaseManager::MatchDownloadWhitelistString(
+    const std::string& str) {
+  NOTREACHED();
+  return true;
+}
+
+bool RemoteSafeBrowsingDatabaseManager::MatchInclusionWhitelistUrl(
+    const GURL& url) {
+  NOTREACHED();
+  return true;
+}
+
+bool RemoteSafeBrowsingDatabaseManager::IsMalwareKillSwitchOn() {
+  NOTREACHED();
+  return true;
+}
+
+bool RemoteSafeBrowsingDatabaseManager::IsCsdWhitelistKillSwitchOn() {
+  NOTREACHED();
+  return true;
+}
+
+SafeBrowsingProtocolManagerDelegate*
+RemoteSafeBrowsingDatabaseManager::GetProtocolManagerDelegate() {
+  return NULL;
+}
+
+bool RemoteSafeBrowsingDatabaseManager::CheckBrowseUrl(const GURL& url,
+                                                       Client* client) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  if (!enabled_)
+    return true;
+
+  if (!CanCheckUrl(url))
+    return true;  // Safe, continue right away.
+
+  scoped_refptr<ClientRequest> req = new ClientRequest();

[mattm, 2015/05/06 02:42:45]

Refcounting is definitely more common in chrome, but still generally best
avoided where possible. Seems like this would work with having the callback take
a weakptr instead of refcounting.

[Nathan Parker, 2015/05/06 22:27:36]

Good idea.  I think that's what you were suggesting on the doc, now that you
describe it this way. 
Done.

+  req->db_manager = this;
+  req->client = client;
+  req->url = url;
+
+  std::vector<SBThreatType> threat_types { SB_THREAT_TYPE_URL_MALWARE };
+
+  VLOG(1) << "Checking for client " << client << " and URL " << url;
+  bool started = api_handler_.StartURLCheck(
+      base::Bind(&ClientRequest::OnRequestDone, req), url, threat_types);
+  if (!started) {
+    LOG(DFATAL) << "Failed to start Safe Browsing request";
+    return true;
+  }
+
+  // Now api_handler_ holds a ref via the callback, and we hold a ref here.
+  current_requests_.push_back(req);
+
+  // Defer the resource load.
+  return false;
+}
+
+void RemoteSafeBrowsingDatabaseManager::ClientRequest::OnRequestDone(
+    SBThreatType matched_threat_type,
+    const std::string& metadata) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  VLOG(1) << "OnRequestDone for client " << client << " and URL " << url;
+  if (!client)

[mattm, 2015/05/06 02:42:45]

if you do it with weakptrs I think you can also get rid of the setting
client=NULL stuff, and just delete the ClientRequest as soon as it finishes or
is canceled.

[Nathan Parker, 2015/05/06 22:27:36]

Done.

+    return;  // Already canceled.
+  client->OnCheckBrowseUrlResult(url, matched_threat_type, metadata);
+  db_manager->CancelCheck(client);
+}
+
+void RemoteSafeBrowsingDatabaseManager::CancelCheck(Client* client) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  DCHECK(enabled_);
+  for (auto itr = current_requests_.begin(); itr != current_requests_.end();
+       ++itr) {
+    if ((*itr)->client == client) {
+      // Mark the req as canceled.
+      (*itr)->client = NULL;
+      VLOG(1) << "Canceling check for URL " << (*itr)->url;
+      current_requests_.erase(itr);
+      return;
+    }
+  }
+  NOTREACHED();
+}
+
+void RemoteSafeBrowsingDatabaseManager::StartOnIOThread() {
+  VLOG(1) << "RemoteSafeBrowsing starting";
+  enabled_ = true;
+}
+
+void RemoteSafeBrowsingDatabaseManager::StopOnIOThread(bool shutdown) {
+  // |shutdown| is not used.
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  VLOG(1) << "RemoteSafeBrowsing stopping";
+
+  // Call back and remove any remaining clients. This modifies
+  // |current_requests_|, so make a copy first.
+  std::vector<scoped_refptr<ClientRequest>> to_callback = current_requests_;
+  for (auto req : to_callback) {
+    VLOG(1) << "Stopping: Invoking unfinished req for URL " << req->url;
+    req->OnRequestDone(SB_THREAT_TYPE_SAFE, std::string());
+  }
+  enabled_ = false;
+}
+