Implement on demand quad rasterization for PicturePiles.

cc/draw_quad.cc

Index: cc/draw_quad.cc
diff --git a/cc/draw_quad.cc b/cc/draw_quad.cc
index 47f9aa0e0b123d62cc7e058bb01f4163e45f83b6..f27adafdf48253d7d5d9e83ede3c7db2adff9de0 100644
--- a/cc/draw_quad.cc
+++ b/cc/draw_quad.cc
@@ -8,6 +8,7 @@
 #include "cc/checkerboard_draw_quad.h"
 #include "cc/debug_border_draw_quad.h"
 #include "cc/io_surface_draw_quad.h"
+#include "cc/picture_draw_quad.h"
 #include "cc/render_pass_draw_quad.h"
 #include "cc/solid_color_draw_quad.h"
 #include "cc/stream_video_draw_quad.h"
@@ -80,6 +81,9 @@ scoped_ptr<DrawQuad> DrawQuad::Copy(
     case YUV_VIDEO_CONTENT:
       copy_quad.reset(TypedCopy<YUVVideoDrawQuad>(this));
       break;
+    case PICTURE_CONTENT:
+      copy_quad.reset(TypedCopy<PictureDrawQuad>(this));
+      break;
     case RENDER_PASS:  // RenderPass quads have their own copy() method.
     case INVALID:
       LOG(FATAL) << "Invalid DrawQuad material " << material;