Fix SkTextBlob offset semantics.

experimental/PdfViewer/SkTrackDevice.h

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkTrackDevice_DEFINED
 #define SkTrackDevice_DEFINED
 
@@ skipping 102 matching lines @@
     }
 
     virtual void drawText(const SkDraw& dummy1, const void* text, size_t len,
                           SkScalar x, SkScalar y, const SkPaint& paint) {
         before();
         INHERITED::drawText(dummy1, text, len, x, y, paint);
         after();
     }
 
     virtual void drawPosText(const SkDraw& dummy1, const void* text, size_t len,
-                             const SkScalar pos[], SkScalar constY,
-                             int scalarsPerPos, const SkPaint& paint) {
+                             const SkScalar pos[], int scalarsPerPos,
+                             const SkPoint& offset, const SkPaint& paint) {
         before();
-        INHERITED::drawPosText(dummy1, text, len, pos, constY, scalarsPerPos, paint);
+        INHERITED::drawPosText(dummy1, text, len, pos, scalarsPerPos, offset, paint);
         after();
     }
 
     virtual void drawTextOnPath(const SkDraw& dummy1, const void* text, size_t len,
                                 const SkPath& path, const SkMatrix* matrix,
                                 const SkPaint& paint)  {
         before();
         INHERITED::drawTextOnPath(dummy1, text, len, path, matrix, paint);
         after();
     }
@@ skipping 30 matching lines @@
         }
     }
 
 private:
     SkTracker* fTracker;
 
     typedef SkBitmapDevice INHERITED;
 };
 
 #endif  // SkTrackDevice_DEFINED