debugger: The DebuggerEngine refactoring.

This replaces the (de facto) singleton engines and data handlers by classes
that are instantiated per run. The DebuggerRunControl will now create an
object of (a class derived from) DebuggerEngine that contains all the relevant
"dynamic" data.

DebuggerManager is no more. The "singleton" bits are merged into DebuggerPlugin,
whereas the data bits went to DebuggerEngine.

There is no formal notion of a "current" DebuggerEngine. However, as there's
only one DebuggerEngine at a time that has its data models connected to the
view, there's still some "de facto" notion of a "current" engine. Calling
SomeModel::setData(int role, QVariant data) with custom role is used as the
primary dispatch mechanism from the views to the "current" data models
(and the engine, as all data models know their engine).

src/plugins/debugger/stackwindow.h

@@ -33,17 +33,14 @@
 #include <QtGui/QTreeView>
 
 namespace Debugger {
-class DebuggerManager;
-
 namespace Internal {
-class DisassemblerViewAgent;
 
 class StackWindow : public QTreeView
 {
     Q_OBJECT
 
 public:
-    StackWindow(DebuggerManager *manager, QWidget *parent = 0);
+    explicit StackWindow(QWidget *parent = 0);
     ~StackWindow();
 
 public slots:
@@ -54,13 +51,16 @@ private slots:
     void rowActivated(const QModelIndex &index);
     void setAlternatingRowColorsHelper(bool on) { setAlternatingRowColors(on); }
     void showAddressColumn(bool on);
+    void reloadFullStack();
 
 private:
     void contextMenuEvent(QContextMenuEvent *ev);
     void copyContentsToClipboard();
 
-    DebuggerManager *m_manager;
-    DisassemblerViewAgent *m_disassemblerAgent;
+    void setModelData(int role, const QVariant &value = QVariant(),
+        const QModelIndex &index = QModelIndex());
+    QVariant modelData(int role, const QModelIndex &index = QModelIndex());
+
     bool m_alwaysResizeColumnsToContents;
 };