Ensure camera system correctly consumes events when it is active (#2346)

* add typename for struct initializer

Signed-off-by: hultonha <hultonha@amazon.co.uk>

* fix for ensuring while the camera is 'active', events are consumed and not propagated

Signed-off-by: hultonha <hultonha@amazon.co.uk>

* refactor how we decide which priority to repsond to events to

Signed-off-by: hultonha <hultonha@amazon.co.uk>

* also -> only

Signed-off-by: hultonha <hultonha@amazon.co.uk>

Code/Framework/AzFramework/AzFramework/Viewport/CameraInput.cpp

@@ -147,7 +147,9 @@ namespace AzFramework
             m_scrollDelta = scroll->m_delta;
         }
 
-        return m_cameras.HandleEvents(event, m_motionDelta, m_scrollDelta);
+        m_handlingEvents = m_cameras.HandleEvents(event, m_motionDelta, m_scrollDelta);
+
+        return m_handlingEvents;
     }
 
     Camera CameraSystem::StepCamera(const Camera& targetCamera, const float deltaTime)

Code/Framework/AzFramework/AzFramework/Viewport/CameraInput.h

@@ -262,12 +262,14 @@ namespace AzFramework
     public:
         bool HandleEvents(const InputEvent& event);
         Camera StepCamera(const Camera& targetCamera, float deltaTime);
+        bool HandlingEvents() const { return m_handlingEvents; }
 
         Cameras m_cameras; //!< Represents a collection of camera inputs that together provide a camera controller.
 
     private:
         ScreenVector m_motionDelta; //!< The delta used for look/orbit/pan (rotation + translation) - two dimensional.
         float m_scrollDelta = 0.0f; //!< The delta used for dolly/movement (translation) - one dimensional.
+        bool m_handlingEvents = false; //!< Is the camera system currently handling events (events are consumed and not propagated).
     };
 
     //! A camera input to handle motion deltas that can rotate or orbit the camera.