Fix several viewport issues (#1045)

* Fix some FOV calculation viewport issues:
-Avoid calculating FOV if we've got an invalid viewport
-Don't override game mode FOV, let the active camera components manage it instead

* Fix viewport font positioning

This updates code in a few places to respect an API change/fix made to AtomFont - also switched the default value of m_virtual800x600ScreenSize to false as it's really behavior you want to opt into

* Don't activate CameraComponentController when in the Editor / not in game mode

Gems/Camera/Code/Source/EditorCameraComponent.cpp

@@ -34,20 +34,9 @@ namespace Camera
         auto controllerConfig = m_controller.GetConfiguration();
         controllerConfig.m_editorEntityId = GetEntityId().operator AZ::u64();
 
-        // The Editor manages active camera state, so while we're in Editor we explicitly
-        // disable the request to make this the active view at edit component activation time.
-        bool prevShouldActivateViewOnActivation = controllerConfig.m_makeActiveViewOnActivation;
-        controllerConfig.m_makeActiveViewOnActivation = false; 
-
-        m_controller.SetConfiguration(controllerConfig);
-
         // Call base class activate, which in turn calls Activate on our controller.
         EditorCameraComponentBase::Activate();
 
-        // Reset the original `m_makeActiveViewOnActivation' setting, so that the intended value is serialized, used in BuildGameEntity, etc.
-        controllerConfig.m_makeActiveViewOnActivation = prevShouldActivateViewOnActivation;
-        m_controller.SetConfiguration(controllerConfig);
-
         AzFramework::EntityDebugDisplayEventBus::Handler::BusConnect(GetEntityId());
         EditorCameraNotificationBus::Handler::BusConnect();
         EditorCameraViewRequestBus::Handler::BusConnect(GetEntityId());