Expose GeolocationProvider in Content API. This removes the recently introduced usage of internal content classes from chrome.

I simplified things a bit in the process. I removed GeolocationObserverOptions since all we need is a boolean (it's been like that for a long time). I also switched from the one-method GeolocationObserver to a callback. This also means that there's one way to get location info, compared to before when there were two ways (interface+callback).

BUG=237552
R=bulach@chromium.org, joth@chromium.org

Review URL: https://codereview.chromium.org/14688015

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@198751 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 117 insertions, 0 deletions

diff --git a/content/browser/geolocation/geolocation_provider_impl.h b/content/browser/geolocation/geolocation_provider_impl.h
new file mode 100644
index 0000000..d4b5afb
--- /dev/null
+++ b/content/browser/geolocation/geolocation_provider_impl.h
@@ -0,0 +1,117 @@
+// Copyright (c) 2012 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 CONTENT_BROWSER_GEOLOCATION_GEOLOCATION_PROVIDER_IMPL_H_
+#define CONTENT_BROWSER_GEOLOCATION_GEOLOCATION_PROVIDER_IMPL_H_
+
+#include <list>
+#include <vector>
+
+#include "base/basictypes.h"
+#include "base/callback_forward.h"
+#include "base/compiler_specific.h"
+#include "base/threading/thread.h"
+#include "content/common/content_export.h"
+#include "content/public/browser/geolocation_provider.h"
+#include "content/public/common/geoposition.h"
+
+template<typename Type> struct DefaultSingletonTraits;
+
+namespace content {
+class GeolocationArbitrator;
+class GeolocationProviderTest;
+
+// This is the main API to the geolocation subsystem. The application will hold
+// a single instance of this class and can register multiple clients to be
+// notified of location changes:
+// * Observers are registered by AddLocationUpdateCallback() and will keep
+//   receiving updates
+//   until unregistered by RemoveLocationUpdateCallback().
+// * Callbacks are registered by RequestCallback() and will be called exactly
+//   once when the next update becomes available.
+// The application must instantiate the GeolocationProvider on the IO thread and
+// must communicate with it on the same thread.
+// The underlying location arbitrator will only be enabled whilst there is at
+// least one registered observer or pending callback. The arbitrator and the
+// location providers it uses run on a separate Geolocation thread.
+class CONTENT_EXPORT GeolocationProviderImpl
+    : public NON_EXPORTED_BASE(GeolocationProvider),
+      public base::Thread {
+ public:
+  // GeolocationProvider implementation:
+  virtual void AddLocationUpdateCallback(const LocationUpdateCallback& callback,
+                                         bool use_high_accuracy) OVERRIDE;
+  virtual bool RemoveLocationUpdateCallback(
+      const LocationUpdateCallback& callback) OVERRIDE;
+  virtual void UserDidOptIntoLocationServices() OVERRIDE;
+
+  bool LocationServicesOptedIn() const;
+
+  // Overrides the location for automation/testing. Suppresses any further
+  // updates from the actual providers and sends an update with the overridden
+  // position to all registered clients.
+  void OverrideLocationForTesting(const Geoposition& override_position);
+
+  // Callback from the GeolocationArbitrator. Public for testing.
+  void OnLocationUpdate(const Geoposition& position);
+
+  // Gets a pointer to the singleton instance of the location relayer, which
+  // is in turn bound to the browser's global context objects. This must only be
+  // called on the IO thread so that the GeolocationProviderImpl is always
+  // instantiated on the same thread. Ownership is NOT returned.
+  static GeolocationProviderImpl* GetInstance();
+
+ protected:
+  friend struct DefaultSingletonTraits<GeolocationProviderImpl>;
+  GeolocationProviderImpl();
+  virtual ~GeolocationProviderImpl();
+
+  // Useful for injecting mock geolocation arbitrator in tests.
+  virtual GeolocationArbitrator* CreateArbitrator();
+
+ private:
+  typedef std::pair<LocationUpdateCallback, bool> LocationUpdateInfo;
+  typedef std::list<LocationUpdateInfo> CallbackList;
+
+  bool OnGeolocationThread() const;
+
+  // Start and stop providers as needed when clients are added or removed.
+  void OnClientsChanged();
+
+  // Stops the providers when there are no more registered clients. Note that
+  // once the Geolocation thread is started, it will stay alive (but sitting
+  // idle without any pending messages).
+  void StopProviders();
+
+  // Starts the geolocation providers or updates their options (delegates to
+  // arbitrator).
+  void StartProviders(bool use_high_accuracy);
+
+  // Updates the providers on the geolocation thread, which must be running.
+  void InformProvidersPermissionGranted();
+
+  // Notifies all registered clients that a position update is available.
+  void NotifyClients(const Geoposition& position);
+
+  // Thread
+  virtual void Init() OVERRIDE;
+  virtual void CleanUp() OVERRIDE;
+
+  // Only used on the IO thread
+  CallbackList callbacks_;
+  bool user_did_opt_into_location_services_;
+  Geoposition position_;
+
+  // True only in testing, where we want to use a custom position.
+  bool ignore_location_updates_;
+
+  // Only to be used on the geolocation thread.
+  GeolocationArbitrator* arbitrator_;
+
+  DISALLOW_COPY_AND_ASSIGN(GeolocationProviderImpl);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_GEOLOCATION_GEOLOCATION_PROVIDER_IMPL_H_