Bug1917: TrackPanel should keep focus after click or drag...

... though ruler won't, and if you start to drag in TrackPanel but abort it
with the ESC key, that too returns focus

src/CellularPanel.cpp

@@ -94,7 +94,7 @@ void CellularPanel::HandleInterruptedDrag()
    }
 }
 
-void CellularPanel::Uncapture(wxMouseState *pState)
+void CellularPanel::Uncapture(bool escaping, wxMouseState *pState)
 {
    auto state = ::wxGetMouseState();
    if (!pState) {
@@ -107,12 +107,14 @@ void CellularPanel::Uncapture(wxMouseState *pState)
       ReleaseMouse();
    HandleMotion( *pState );
 
-   auto lender = GetProject()->mFocusLender.get();
-   if (lender)
-      lender->SetFocus();
+   if (escaping || !TakesFocus()) {
+      auto lender = GetProject()->mFocusLender.get();
+      if (lender)
+         lender->SetFocus();
+   }
 }
 
-bool CellularPanel::CancelDragging()
+bool CellularPanel::CancelDragging( bool escaping )
 {
    auto &state = *mState;
    if (state.mUIHandle) {
@@ -127,7 +129,7 @@ bool CellularPanel::CancelDragging()
             refreshResult | state.mMouseOverUpdateFlags );
       state.mpClickedCell.reset();
       state.mUIHandle.reset(), handle.reset(), ClearTargets();
-      Uncapture();
+      Uncapture( escaping );
       return true;
    }
    return false;
@@ -148,7 +150,7 @@ bool CellularPanel::HandleEscapeKey(bool down)
 
    auto &state = *mState;
    if (state.mUIHandle) {
-      CancelDragging();
+      CancelDragging( true );
       return true;
    }
 
@@ -690,7 +692,7 @@ try
          ::wxGetMouseState().ButtonIsDown(wxMOUSE_BTN_ANY);
 
       if(!buttons) {
-         CancelDragging();
+         CancelDragging( false );
 
 #if defined(__WXMAC__)
 
@@ -717,7 +719,7 @@ try
             // Drag decided to abort itself
             state.mUIHandle.reset(), handle.reset(), ClearTargets();
             state.mpClickedCell.reset();
-            Uncapture( &event );
+            Uncapture( false, &event );
          }
          else {
             UpdateMouseState(event);
@@ -753,15 +755,15 @@ try
    }
 
    if (event.ButtonUp())
-      Uncapture();
+      Uncapture( false );
 }
 catch( ... )
 {
    // Abort any dragging, as if by hitting Esc
-   if ( CancelDragging() )
+   if ( CancelDragging( true ) )
       ;
    else {
-      Uncapture();
+      Uncapture( true );
       Refresh(false);
    }
    throw;