Paint: remove readPixels.

cc/paint/paint_canvas.h

Index: cc/paint/paint_canvas.h
diff --git a/cc/paint/paint_canvas.h b/cc/paint/paint_canvas.h
index 8796447359b3b69417dec4e10a30bd139e374687..daacc3017889050f52f4facfe35ae8b0053ba22b 100644
--- a/cc/paint/paint_canvas.h
+++ b/cc/paint/paint_canvas.h
@@ -34,13 +34,6 @@ class CC_PAINT_EXPORT PaintCanvas {
   virtual void flush() = 0;
 
   virtual SkISize getBaseLayerSize() const = 0;
-  virtual bool readPixels(const SkImageInfo& dest_info,
-                          void* dest_pixels,
-                          size_t dest_row_bytes,
-                          int src_x,
-                          int src_y) = 0;
-  virtual bool readPixels(SkBitmap* bitmap, int src_x, int src_y) = 0;
-  virtual bool readPixels(const SkIRect& srcRect, SkBitmap* bitmap) = 0;
   virtual bool writePixels(const SkImageInfo& info,
                            const void* pixels,
                            size_t row_bytes,