2096: Windows & Mac high quality Change Pitch/Tempo preview

Problem:
Preview plays the original, and removes the selection.
This appears to have been caused by the commit: 0aad028

Fix: revert that commit. Note that in the #ifdef EXPERIMENTAL_SPECTRAL_EDITING code has not been reinstated.
I have not looked at why the commit caused the problem, just reverted it.

src/effects/ChangePitch.cpp

@@ -211,11 +211,12 @@ bool EffectChangePitch::Process()
    if (mUseSBSMS)
    {
       double pitchRatio = 1.0 + m_dPercentChange / 100.0;
+      SelectedRegion region(mT0, mT1);
       EffectSBSMS proxy;
       proxy.mProxyEffectName = XO("High Quality Pitch Change");
       proxy.setParameters(1.0, pitchRatio);
 
-      return Delegate(proxy, mUIParent, false);
+      return Delegate(proxy, mUIParent, &region, false);
    }
    else
 #endif

src/effects/ChangeTempo.cpp

@@ -197,10 +197,11 @@ bool EffectChangeTempo::Process()
    if (mUseSBSMS)
    {
       double tempoRatio = 1.0 + m_PercentChange / 100.0;
+      SelectedRegion region(mT0, mT1);
       EffectSBSMS proxy;
       proxy.mProxyEffectName = XO("High Quality Tempo Change");
       proxy.setParameters(tempoRatio, 1.0);
-      success = Delegate(proxy, mUIParent, false);
+      success = Delegate(proxy, mUIParent, &region, false);
    }
    else
 #endif

src/effects/Effect.cpp

@@ -1180,7 +1180,6 @@ bool Effect::DoEffect(wxWindow *parent,
 
    mOutputTracks.reset();
 
-   mpSelectedRegion = selectedRegion;
    mFactory = factory;
    mProjectRate = projectRate;
    mTracks = list;
@@ -1289,10 +1288,11 @@ bool Effect::DoEffect(wxWindow *parent,
    return returnVal;
 }
 
-bool Effect::Delegate( Effect &delegate, wxWindow *parent, bool shouldPrompt)
+bool Effect::Delegate( Effect &delegate,
+   wxWindow *parent, SelectedRegion *selectedRegion, bool shouldPrompt)
 {
    return delegate.DoEffect( parent, mProjectRate, mTracks, mFactory,
-      mpSelectedRegion, shouldPrompt );
+      selectedRegion, shouldPrompt );
 }
 
 // All legacy effects should have this overridden

src/effects/Effect.h

@@ -249,7 +249,8 @@ class AUDACITY_DLL_API Effect /* not final */ : public wxEvtHandler,
                  TrackFactory *factory, SelectedRegion *selectedRegion,
                  bool shouldPrompt = true);
 
-   bool Delegate( Effect &delegate, wxWindow *parent, bool shouldPrompt);
+   bool Delegate( Effect &delegate,
+      wxWindow *parent, SelectedRegion *selectedRegion, bool shouldPrompt);
 
    // Realtime Effect Processing
    /* not virtual */ bool RealtimeAddProcessor(int group, unsigned chans, float rate);
@@ -457,7 +458,6 @@ protected:
    double         mProjectRate; // Sample rate of the project - NEW tracks should
                                // be created with this rate...
    double         mSampleRate;
-   SelectedRegion *mpSelectedRegion{};
    TrackFactory   *mFactory;
    const TrackList *inputTracks() const { return mTracks; }
    std::shared_ptr<TrackList> mOutputTracks; // used only if CopyInputTracks() is called.

src/effects/nyquist/Nyquist.cpp

@@ -968,7 +968,8 @@ bool NyquistEffect::ShowInterface(wxWindow *parent, bool forceModal)
 
    effect.SetCommand(mInputCmd);
    effect.mDebug = (mUIResultID == eDebugID);
-   bool result = Delegate(effect, parent, true);
+   SelectedRegion region(mT0, mT1);
+   bool result = Delegate(effect, parent, &region, true);
    mT0 = effect.mT0;
    mT1 = effect.mT1;
    return result;