add asScalars() to document when we want to treat SkPoint or SkRect as an array

trunk/include/core/SkPoint.h

 /*
  * Copyright 2006 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkPoint_DEFINED
 #define SkPoint_DEFINED
 
@@ skipping 486 matching lines @@
         SkScalar tmp = vec.fX;
         if (kRight_Side == side) {
             fX = -vec.fY;
             fY = tmp;
         } else {
             SkASSERT(kLeft_Side == side);
             fX = vec.fY;
             fY = -tmp;
         }
     }
+
+    /**
+     *  cast-safe way to treat the point as an array of (2) SkScalars.
+     */
+    const SkScalar* asScalars() const { return &fX; }
 };
 
 typedef SkPoint SkVector;
 
 #endif