cc: Tell the LayerTreeHost that the filter context is needed.

cc/output/software_renderer.cc

 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/output/software_renderer.h"
 
 #include "base/debug/trace_event.h"
 #include "cc/base/math_util.h"
 #include "cc/output/compositor_frame.h"
 #include "cc/output/compositor_frame_ack.h"
 #include "cc/output/compositor_frame_metadata.h"
 #include "cc/output/copy_output_request.h"
 #include "cc/output/output_surface.h"
 #include "cc/output/software_output_device.h"
 #include "cc/quads/checkerboard_draw_quad.h"
 #include "cc/quads/debug_border_draw_quad.h"
 #include "cc/quads/picture_draw_quad.h"
 #include "cc/quads/render_pass_draw_quad.h"
 #include "cc/quads/solid_color_draw_quad.h"
 #include "cc/quads/texture_draw_quad.h"
 #include "cc/quads/tile_draw_quad.h"
 #include "skia/ext/opacity_draw_filter.h"
 #include "third_party/skia/include/core/SkCanvas.h"
 #include "third_party/skia/include/core/SkColor.h"
+#include "third_party/skia/include/core/SkImageFilter.h"
 #include "third_party/skia/include/core/SkMatrix.h"
 #include "third_party/skia/include/core/SkShader.h"
 #include "third_party/skia/include/effects/SkLayerRasterizer.h"
 #include "ui/gfx/rect_conversions.h"
 #include "ui/gfx/skia_util.h"
 #include "ui/gfx/transform.h"
 
 namespace cc {
 
 namespace {
@@ skipping 512 matching lines @@
     EnsureBackbuffer();
   else
     DiscardBackbuffer();
 }
 
 void SoftwareRenderer::SetDiscardBackBufferWhenNotVisible(bool discard) {
   // The software renderer always discards the backbuffer when not visible.
 }
 
 }  // namespace cc