Add skia::RefPtr class to wrap ref counted classes from Skia.

cc/gl_renderer.cc

Index: cc/gl_renderer.cc
diff --git a/cc/gl_renderer.cc b/cc/gl_renderer.cc
index 94f8d83124f945b5118af3f5b1d07a7bbcdc5fba..b0fb067775b63741d0b92d6c3ab34bc5e0d78008 100644
--- a/cc/gl_renderer.cc
+++ b/cc/gl_renderer.cc
@@ -533,7 +533,7 @@ void GLRenderer::drawRenderPassQuad(DrawingFrame& frame, const RenderPassDrawQua
     // Apply filters to the contents texture.
     SkBitmap filterBitmap;
     if (renderPass->filter) {
-        filterBitmap = applyImageFilter(this, renderPass->filter, contentsTexture, m_client->hasImplThread());
+        filterBitmap = applyImageFilter(this, renderPass->filter.get(), contentsTexture, m_client->hasImplThread());
     } else {
         filterBitmap = applyFilters(this, renderPass->filters, contentsTexture, m_client->hasImplThread());
     }