ProjectAudioManager doesn't use ProjectWindow, which doesn't use...

ControlToolBar, after we make a system to register functions that calculate
necessary minimum widths for status bar fields.

Also let Scrubbing.cpp register its own strings.

Also be sure to size the status field sufficiently for "Playing at Speed".

src/ProjectWindow.cpp

@@ -27,7 +27,6 @@ Paul Licameli split from AudacityProject.cpp
 #include "WaveTrack.h"
 #include "prefs/ThemePrefs.h"
 #include "prefs/TracksPrefs.h"
-#include "toolbars/ControlToolBar.h"
 #include "toolbars/ToolManager.h"
 #include "tracks/ui/Scrubbing.h"
 #include "tracks/ui/TrackView.h"
@@ -815,13 +814,7 @@ void ProjectWindow::Init()
 #endif
    mIconized = false;
 
-   int widths[] = {
-      0,
-      ControlToolBar::Get( project ).WidthForStatusBar(statusBar),
-      -1,
-      150
-   };
-   statusBar->SetStatusWidths(4, widths);
+   UpdateStatusWidths();
    wxString msg = wxString::Format(_("Welcome to Audacity version %s"),
                                    AUDACITY_VERSION_STRING);
    statusBar->SetStatusText(msg, mainStatusBarField);
@@ -1341,6 +1334,33 @@ bool ProjectWindow::IsIconized() const
    return mIconized;
 }
 
+void ProjectWindow::UpdateStatusWidths()
+{
+   enum { nWidths = nStatusBarFields + 1 };
+   int widths[ nWidths ]{ 0 };
+   widths[ rateStatusBarField ] = 150;
+   const auto statusBar = GetStatusBar();
+   const auto &functions = ProjectStatus::GetStatusWidthFunctions();
+   // Start from 1 not 0
+   // Specifying a first column always of width 0 was needed for reasons
+   // I forget now
+   for ( int ii = 1; ii <= nStatusBarFields; ++ii ) {
+      int &width = widths[ ii ];
+      for ( const auto &function : functions ) {
+         auto results =
+            function( mProject, static_cast< StatusBarField >( ii ) );
+         for ( const auto &string : results.first ) {
+            int w;
+            statusBar->GetTextExtent(string, &w, nullptr);
+            width = std::max<int>( width, w + results.second );
+         }
+      }
+   }
+   // The main status field is not fixed width
+   widths[ mainStatusBarField ] = -1;
+   statusBar->SetStatusWidths( nWidths, widths );
+}
+
 void ProjectWindow::OnIconize(wxIconizeEvent &event)
 {
    //JKC: On Iconizing we get called twice.  Don't know