ClearCase: Don't show Hijack button for dynamic view

The Hijack button (makeWriteableButton) should only
be shown for snapshot views.

Change-Id: I809981885d18b6057d82f73b5104b0f1041cd255
Reviewed-by: Orgad Shaneh <orgads@gmail.com>
Reviewed-by: Tobias Hunger <tobias.hunger@digia.com>

src/plugins/coreplugin/iversioncontrol.h

@@ -50,7 +50,7 @@ public:
     Q_DECLARE_FLAGS(SettingsFlags, SettingsFlag)
 
     enum Operation {
-        AddOperation, DeleteOperation, OpenOperation, MoveOperation,
+        AddOperation, DeleteOperation, MoveOperation,
         CreateRepositoryOperation,
         SnapshotOperations,
         AnnotateOperation,
@@ -58,6 +58,12 @@ public:
         GetRepositoryRootOperation
         };
 
+    enum OpenSupportMode {
+        NoOpen,        /*!< Files can be edited without noticing the VCS */
+        OpenOptional,  /*!< Files can be opened by the VCS, or hijacked */
+        OpenMandatory  /*!< Files must always be opened by the VCS */
+    };
+
     explicit IVersionControl(QObject *parent = 0) : QObject(parent) {}
     virtual ~IVersionControl() {}
 
@@ -85,6 +91,11 @@ public:
      */
     virtual bool supportsOperation(Operation operation) const = 0;
 
+    /*!
+     * Returns the open support mode.
+     */
+    virtual OpenSupportMode openSupportMode() const;
+
     /*!
      * Called prior to save, if the file is read only. Should be implemented if
      * the scc requires a operation before editing the file, e.g. 'p4 edit'