Region scrollbar fix!

Now scrollbars correctly hide and show, making space for the actual contents
in a region. It solves several old hacks, and puts view2d code a bit more
back in control as well. 

Implementation notes:

- The view2d mask feature is working again
- The #define V2D_SCROLL_HORIZONTAL_HIDE means: "turn on hiding".
- Code for UI_view2d_region_reinit() is enforcing better standard view settings

But... two hack/patches needed to be added:

- Region panel drawing: if after generating the button panels it appears
  a scroller hides or reveils, it calls all the generating code again.
  (a simple scale doesn't work due to rounding differences in layout code)

- View2d code that maps 'tot' and 'cur' rects: if this code detects that
  the mask changes, it calcs the map code again.

Also a bugfix (issue in 2.65)

- The left/bottom area split widget was drawing 1 pixel too large sometimes, 
  leaving bad trails on moving area dividers.

2 files changed, 1 insertions, 1 deletions

diff --git a/source/blender/editors/include/UI_interface.h b/source/blender/editors/include/UI_interface.h
index 90f8779b2c7..9a04138e72e 100644
--- a/source/blender/editors/include/UI_interface.h
+++ b/source/blender/editors/include/UI_interface.h
@@ -658,6 +658,7 @@ void uiDrawPanels(const struct bContext *C, struct ARegion *ar);
 
 struct Panel *uiBeginPanel(struct ScrArea *sa, struct ARegion *ar, uiBlock *block, struct PanelType *pt, int *open);
 void uiEndPanel(uiBlock *block, int width, int height);
+void uiScalePanels(struct ARegion *ar, float new_width);
 
 /* Handlers
  *
diff --git a/source/blender/editors/include/UI_view2d.h b/source/blender/editors/include/UI_view2d.h
index 3ae1e93dc3d..81a0f526049 100644
--- a/source/blender/editors/include/UI_view2d.h
+++ b/source/blender/editors/include/UI_view2d.h
@@ -148,7 +148,6 @@ typedef struct View2DScrollers View2DScrollers;
 void UI_view2d_region_reinit(struct View2D *v2d, short type, int winx, int winy);
 
 void UI_view2d_curRect_validate(struct View2D *v2d);
-void UI_view2d_curRect_validate_resize(struct View2D *v2d, int resize);
 void UI_view2d_curRect_reset(struct View2D *v2d);
 void UI_view2d_sync(struct bScreen *screen, struct ScrArea *sa, struct View2D *v2dcur, int flag);