Implements part of Device Motion in the Renderer

content/browser/device_orientation/provider.h

 // 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_DEVICE_ORIENTATION_PROVIDER_H_
 #define CONTENT_BROWSER_DEVICE_ORIENTATION_PROVIDER_H_
 
 #include "base/memory/ref_counted.h"
 #include "content/common/content_export.h"
 
 namespace device_orientation {
 
+class Motion;
 class Orientation;
 
 class CONTENT_EXPORT Provider : public base::RefCountedThreadSafe<Provider> {
  public:
-  class Observer {
+  // TODO(aousterh): refactor this so that there is only one type of observer
+  // that can handle multiple types of data (motion, orientation, etc.)
+  class MotionObserver {
+   public:
+    virtual void OnMotionUpdate(const Motion& motion) = 0;
+
+   protected:
+    virtual ~MotionObserver() {}
+  };
+
+  class OrientationObserver {

[Steve Block, 2012/07/04 13:58:24]

You might want to do the Oberver -> OrientationObserver rename as a separate
prerequisite change to reduce the size of this diff.

    public:
     // Called when the orientation changes.
     // An Observer must not synchronously call Provider::RemoveObserver
     // or Provider::AddObserver when this is called.
     virtual void OnOrientationUpdate(const Orientation& orientation) = 0;
 
    protected:
-    virtual ~Observer() {}
+    virtual ~OrientationObserver() {}
   };
 
   // Returns a pointer to the singleton instance of this class.
   // The caller should store the returned pointer in a scoped_refptr.
   // The Provider instance is lazily constructed when GetInstance() is called,
   // and destructed when the last scoped_refptr referring to it is destructed.
   static Provider* GetInstance();
 
   // Inject a mock Provider for testing. Only a weak pointer to the injected
   // object will be held by Provider, i.e. it does not itself contribute to the
   // injected object's reference count.
   static void SetInstanceForTests(Provider* provider);
 
   // Get the current instance. Used for testing.
   static Provider* GetInstanceForTests();
 
-  // Note: AddObserver may call back synchronously to the observer with
-  // orientation data.
-  virtual void AddObserver(Observer* observer) = 0;
-  virtual void RemoveObserver(Observer* observer) = 0;
+  // Note: AddMotionObserver and AddOrientationObserver may call back
+  // synchronously to the observer with data.
+  virtual void AddMotionObserver(MotionObserver* observer) = 0;
+  virtual void AddOrientationObserver(OrientationObserver* observer) = 0;
+
+  virtual void RemoveMotionObserver(MotionObserver* observer) = 0;
+  virtual void RemoveOrientationObserver(OrientationObserver* observer) = 0;
 
  protected:
   Provider();
   virtual ~Provider();
 
  private:
   friend class base::RefCountedThreadSafe<Provider>;
   static Provider* instance_;
 
   DISALLOW_COPY_AND_ASSIGN(Provider);
 };
 
 }  // namespace device_orientation
 
 #endif  // CONTENT_BROWSER_DEVICE_ORIENTATION_PROVIDER_H_