Mark a class for export to fix component build for views_unittests on touchui.

views/touchui/touch_selection_controller_impl.h

Index: views/touchui/touch_selection_controller_impl.h
diff --git a/views/touchui/touch_selection_controller_impl.h b/views/touchui/touch_selection_controller_impl.h
index 00ade4103c9f8dc752cbdc9001e3795a1f8b8473..6cb78166f1d79c4325d89aa75aeb9fde774f153c 100644
--- a/views/touchui/touch_selection_controller_impl.h
+++ b/views/touchui/touch_selection_controller_impl.h
@@ -9,12 +9,14 @@
 #include "ui/gfx/point.h"
 #include "views/touchui/touch_selection_controller.h"
 #include "views/view.h"
+#include "views/views_export.h"
 
 namespace views {
 
 // Touch specific implementation of TouchSelectionController. Responsible for
 // displaying selection handles and menu elements relevant in a touch interface.
-class TouchSelectionControllerImpl : public TouchSelectionController {
+class VIEWS_EXPORT TouchSelectionControllerImpl
+    : public TouchSelectionController {
  public:
   // Use TextSelectionController::create().
   explicit TouchSelectionControllerImpl(TouchSelectionClientView* client_view);