Only support left/right maximizing at 50% width when the --ash-enable-alternate-caption-button

ash/wm/workspace/workspace_window_resizer.h

Index: ash/wm/workspace/workspace_window_resizer.h
diff --git a/ash/wm/workspace/workspace_window_resizer.h b/ash/wm/workspace/workspace_window_resizer.h
index 76176b1a2b4a77fa7b1ad3b4a75eafded2a7e282..3b39974e3de0f01f7a1bff1e3f66854e59673e5c 100644
--- a/ash/wm/workspace/workspace_window_resizer.h
+++ b/ash/wm/workspace/workspace_window_resizer.h
@@ -18,7 +18,6 @@ namespace ash {
 namespace internal {
 
 class PhantomWindowController;
-class SnapSizer;
 class WindowSize;
 
 // WindowResizer implementation for workspaces. This enforces that windows are
@@ -74,17 +73,13 @@ class ASH_EXPORT WorkspaceWindowResizer : public WindowResizer {
   // Type of snapping.
   enum SnapType {
     // Snap to the left/right edge of the screen.
-    SNAP_LEFT_EDGE,
-    SNAP_RIGHT_EDGE,
+    SNAP_LEFT,
+    SNAP_RIGHT,
 
     // No snap position.
     SNAP_NONE
   };
 
-  // Returns the final bounds to place the window at. This differs from
-  // the current when snapping.
-  gfx::Rect GetFinalBounds(const gfx::Rect& bounds) const;
-
   // Lays out the attached windows. |bounds| is the bounds of the main window.
   void LayoutAttachedWindows(gfx::Rect* bounds);
 
@@ -187,9 +182,6 @@ class ASH_EXPORT WorkspaceWindowResizer : public WindowResizer {
   // is a grid and the caption is being dragged.
   scoped_ptr<PhantomWindowController> snap_phantom_window_controller_;
 
-  // Used to determine the target position of a snap.
-  scoped_ptr<SnapSizer> snap_sizer_;
-
   // Last SnapType.
   SnapType snap_type_;