Add ctrl+drag feature for allowing resizing window with exact positioning.

ash/wm/window_resizer.h

Index: ash/wm/window_resizer.h
diff --git a/ash/wm/window_resizer.h b/ash/wm/window_resizer.h
index d02be930d374dcb9b61b9691ca1ecb1baf066c80..58a3b5c267249eb71dfc711db48d7eafee69fb5d 100644
--- a/ash/wm/window_resizer.h
+++ b/ash/wm/window_resizer.h
@@ -48,8 +48,9 @@ class ASH_EXPORT WindowResizer {
   static int AlignToGridRoundDown(int location, int grid_size);
 
   // Invoked to drag/move/resize the window. |location| is in the coordinates
-  // of the window supplied to the constructor.
-  virtual void Drag(const gfx::Point& location) = 0;
+  // of the window supplied to the constructor. |event_flags| is the event
+  // flags from mouse event.
+  virtual void Drag(const gfx::Point& location, int event_flags) = 0;
 
   // Invoked to complete the drag.
   virtual void CompleteDrag() = 0;
@@ -96,7 +97,8 @@ class ASH_EXPORT WindowResizer {
 
   static gfx::Rect CalculateBoundsForDrag(
       const Details& details,
-      const gfx::Point& location);
+      const gfx::Point& location,
+      bool disable_snap_to_grid);
 
   static gfx::Rect AdjustBoundsToGrid(const gfx::Rect& bounds,
                                       int grid_size);
@@ -113,17 +115,20 @@ class ASH_EXPORT WindowResizer {
   // Returns the size of the window for the drag.
   static gfx::Size GetSizeForDrag(const Details& details,
                                   int* delta_x,
-                                  int* delta_y);
+                                  int* delta_y,
+                                  bool disable_snap_to_grid);
 
   // Returns the width of the window.
   static int GetWidthForDrag(const Details& details,
                              int min_width,
-                             int* delta_x);
+                             int* delta_x,
+                             bool disable_snap_to_grid);
 
   // Returns the height of the drag.
   static int GetHeightForDrag(const Details& details,
                               int min_height,
-                              int* delta_y);
+                              int* delta_y,
+                              bool disable_snap_to_grid);
 };
 
 }  // namespace aura