Added Header and Footer support using Skia

skia/ext/vector_platform_device_skia.h

Index: skia/ext/vector_platform_device_skia.h
diff --git a/skia/ext/vector_platform_device_skia.h b/skia/ext/vector_platform_device_skia.h
index 7aaa2a29e1da6a9ee187a3f30e9218936b031494..32522583500c2c116a81573305f8ba60a9923e15 100644
--- a/skia/ext/vector_platform_device_skia.h
+++ b/skia/ext/vector_platform_device_skia.h
@@ -79,8 +79,12 @@ class VectorPlatformDeviceSkia : public PlatformDevice {
   virtual void drawDevice(const SkDraw& draw, SkDevice*, int x, int y,
                           const SkPaint&);
 
+  // Sets the drawing area for the device. Subsequent draw calls are
+  // directed to the specific drawing area (margin or content area).
+  virtual void setDrawingArea(SkPDFDevice::DrawingArea area);
+
  protected:
-  virtual SkDevice* onCreateCompatibleDevice(SkBitmap::Config, int width, 
+  virtual SkDevice* onCreateCompatibleDevice(SkBitmap::Config, int width,
                                              int height, bool isOpaque,
                                              Usage usage);