HYDRA-686 : Make MayaHydraSceneIndex manual cleanup call its destructor

lib/mayaHydra/hydraExtensions/sceneIndex/mayaHydraSceneIndex.cpp

@@ -476,16 +476,6 @@ MayaHydraSceneIndex::MayaHydraSceneIndex(
 }
 
 MayaHydraSceneIndex::~MayaHydraSceneIndex()
-{
-    //If you get a crash in a callback with a nullptr for _sceneIndex, 
-    // it may be due to the fact that the _sceneIndex pointer has been nulled as its ref count reached 0 but the destructor is still being called.
-    //You should call RemoveCallbacksAndDeleteAdapters(); before the destructor is called.
-
-    // Remove our pick handler from the pick handler registry.
-    TF_AXIOM(MayaHydra::PickHandlerRegistry::Instance().Unregister(_rprimPath));
-}
-
-void MayaHydraSceneIndex::RemoveCallbacksAndDeleteAdapters()
 {
     //Remove global materials
     if (_mayaDefaultMaterialFallback.IsHolding<HdMaterialNetworkMap>()){
@@ -513,6 +503,9 @@ void MayaHydraSceneIndex::RemoveCallbacksAndDeleteAdapters()
     _materialAdapters.clear();
     _cameraAdapters.clear();
     _renderItemsAdaptersFast.clear();
+
+    // Remove our pick handler from the pick handler registry.
+    TF_AXIOM(MayaHydra::PickHandlerRegistry::Instance().Unregister(_rprimPath));
 }
 
 void MayaHydraSceneIndex::HandleCompleteViewportScene(const MDataServerOperation::MViewportScene& scene, MFrameContext::DisplayStyle ds)

lib/mayaHydra/hydraExtensions/sceneIndex/mayaHydraSceneIndex.h

@@ -109,9 +109,6 @@ class MAYAHYDRALIB_API MayaHydraSceneIndex : public HdRetainedSceneIndex, public
 
     ~MayaHydraSceneIndex();
 
-    //Call this before the destructor is called.
-    void RemoveCallbacksAndDeleteAdapters();
-
     // ------------------------------------------------------------------------
     // Maya Hydra scene producer implementations
     // Propogate scene changes from Maya to Hydra

lib/mayaHydra/mayaPlugin/renderOverride.cpp

@@ -924,7 +924,6 @@ void MtohRenderOverride::_SetRenderPurposeTags(const MayaHydraParams& delegatePa
 void MtohRenderOverride::_ClearMayaHydraSceneIndex()
 {
     _renderIndexProxy->RemoveSceneIndex(_mayaHydraSceneIndex);
-    _mayaHydraSceneIndex->RemoveCallbacksAndDeleteAdapters(); //This should be called before calling _sceneIndex.Reset(); which will call the destructor if the ref count reaches 0
     _mayaHydraSceneIndex.Reset();
 }
 
@@ -1063,7 +1062,6 @@ void MtohRenderOverride::ClearHydraResources(bool fullReset)
     #ifdef CODE_COVERAGE_WORKAROUND
         // Leak the Maya scene index, as its base class HdRetainedSceneIndex
         // destructor crashes under Windows clang code coverage build.
-        _mayaHydraSceneIndex->RemoveCallbacksAndDeleteAdapters();
         _mayaHydraSceneIndex.Reset();
     #else
        _ClearMayaHydraSceneIndex();