[Media Router] Conditionally enable mDNS on Windows.

chrome/browser/media/router/media_router_mojo_impl.h

 // Copyright 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.
 
 #ifndef CHROME_BROWSER_MEDIA_ROUTER_MEDIA_ROUTER_MOJO_IMPL_H_
 #define CHROME_BROWSER_MEDIA_ROUTER_MEDIA_ROUTER_MOJO_IMPL_H_
 
 #include <stdint.h>
 
 #include <deque>
 #include <map>
 #include <set>
 #include <string>
 #include <vector>
 
 #include "base/containers/hash_tables.h"
 #include "base/containers/scoped_ptr_hash_map.h"
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "base/observer_list.h"
 #include "base/thread_task_runner_handle.h"
+#include "build/build_config.h"
 #include "chrome/browser/media/router/issue.h"
 #include "chrome/browser/media/router/issue_manager.h"
 #include "chrome/browser/media/router/media_router.mojom.h"
 #include "chrome/browser/media/router/media_router_base.h"
 #include "chrome/browser/media/router/media_routes_observer.h"
 #include "mojo/public/cpp/bindings/binding.h"
 
 namespace content {
 class BrowserContext;
 }
@@ skipping 55 matching lines @@
   void DetachRoute(const MediaRoute::Id& route_id) override;
   void SendRouteMessage(const MediaRoute::Id& route_id,
                         const std::string& message,
                         const SendRouteMessageCallback& callback) override;
   void SendRouteBinaryMessage(
       const MediaRoute::Id& route_id,
       scoped_ptr<std::vector<uint8_t>> data,
       const SendRouteMessageCallback& callback) override;
   void AddIssue(const Issue& issue) override;
   void ClearIssue(const Issue::Id& issue_id) override;
+  void OnUserGesture() override;
 
   const std::string& media_route_provider_extension_id() const {
     return media_route_provider_extension_id_;
   }
 
   void set_instance_id_for_test(const std::string& instance_id) {
     instance_id_ = instance_id;
   }
 
  private:
@@ skipping 200 matching lines @@
   void AttemptWakeEventPage();
 
   // Sets the reason why we are attempting to wake the extension.  Since
   // multiple tasks may be enqueued for execution each time the extension runs,
   // we record the first such reason.
   void SetWakeReason(MediaRouteProviderWakeReason reason);
 
   // Clears the wake reason after the extension has been awoken.
   void ClearWakeReason();
 
+#if defined(OS_WIN)
+  // Ensures that mDNS discovery is enabled in the MRPM extension. This can be
+  // called many times but the MRPM will only be called once per registration
+  // period.
+  void EnsureMdnsDiscoveryEnabled();
+  void DoEnsureMdnsDiscoveryEnabled();
+
+  // Callback used to enabled mDNS in the MRPM if a firewall prompt will not be
+  // triggered. If a firewall prompt would be triggered, enabling mDNS won't
+  // happen until the user is clearly interacting with MR.
+  void OnFirewallCheckComplete(bool firewall_can_use_local_ports);
+#endif
+
   // Pending requests queued to be executed once component extension
   // becomes ready.
   std::deque<base::Closure> pending_requests_;
 
   base::ScopedPtrHashMap<MediaSource::Id, scoped_ptr<MediaSinksQuery>>
       sinks_queries_;
 
   base::ScopedPtrHashMap<MediaSource::Id, scoped_ptr<MediaRoutesQuery>>
       routes_queries_;
 
@@ skipping 37 matching lines @@
 
   // The last reported sink availability from the media route provider manager.
   interfaces::MediaRouter::SinkAvailability availability_;
 
   int wakeup_attempt_count_;
 
   // Records the current reason the extension is being woken up.  Is set to
   // MediaRouteProviderWakeReason::TOTAL_COUNT if there is no pending reason.
   MediaRouteProviderWakeReason current_wake_reason_;
 
+#if defined(OS_WIN)
+  // A pair of flags to ensure that mDNS discovery is only enabled on Windows
+  // when there will be appropriate context for the user to associate a firewall
+  // prompt with Media Router. |should_enable_mdns_discovery_| can only go from
+  // |false| to |true|. On Windows, |is_mdns_enabled_| is set to |false| in
+  // RegisterMediaRouteProvider and only set to |true| when we successfully call
+  // the extension to enable mDNS.
+  bool is_mdns_enabled_ = false;
+  bool should_enable_mdns_discovery_ = false;
+#endif
+
   base::WeakPtrFactory<MediaRouterMojoImpl> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(MediaRouterMojoImpl);
 };
 
 }  // namespace media_router
 
 #endif  // CHROME_BROWSER_MEDIA_ROUTER_MEDIA_ROUTER_MOJO_IMPL_H_