Utils: Drop SynchronousProcessResponse

Move the remnaining two members into QtcProcessPrivate, its
only user.

Change-Id: I8e0c23e1a56b36b750b5b4bd4e88d762260e42a1
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

src/plugins/vcsbase/vcsbaseplugin.h

@@ -33,8 +33,6 @@
 
 #include <extensionsystem/iplugin.h>
 
-#include <utils/environment.h>
-
 #include <QSharedDataPointer>
 
 QT_BEGIN_NAMESPACE
@@ -43,8 +41,7 @@ class QTextCodec;
 QT_END_NAMESPACE
 
 namespace Utils {
-class CommandLine;
-class SynchronousProcessResponse;
+class Environment;
 } // namespace Utils
 
 namespace Core {