Part 1/3 (compositor) of adding with device scale factor to transport surfaces

cc/output/software_renderer_unittest.cc

Index: cc/output/software_renderer_unittest.cc
diff --git a/cc/output/software_renderer_unittest.cc b/cc/output/software_renderer_unittest.cc
index 4f2d605827dff9a2780478961852ccd1a8303bee..af4d7d1f715f435ce904239c7205238cc84c2fd4 100644
--- a/cc/output/software_renderer_unittest.cc
+++ b/cc/output/software_renderer_unittest.cc
@@ -52,6 +52,9 @@ class SoftwareRendererTest : public testing::Test, public RendererClient {
   virtual gfx::Size DeviceViewportSize() const OVERRIDE {
     return viewport_size_;
   }
+  virtual float DeviceScaleFactor() const OVERRIDE {
+    return 1.f;
+  }
   virtual const LayerTreeSettings& Settings() const OVERRIDE {
     return settings_;
   }