cc: Scale checkerboard quads by the device scale factor.

cc/output/gl_renderer.cc

Index: cc/output/gl_renderer.cc
diff --git a/cc/output/gl_renderer.cc b/cc/output/gl_renderer.cc
index 6142d96408d22e51d47489f905c1280e62ffa635..4cce9322d1e41da765e7ffd3a78c3d766b765248 100644
--- a/cc/output/gl_renderer.cc
+++ b/cc/output/gl_renderer.cc
@@ -565,8 +565,8 @@ void GLRenderer::DrawCheckerboardQuad(const DrawingFrame* frame,
   gfx::Rect tile_rect = quad->rect;
   float tex_offset_x = tile_rect.x() % checkerboard_width;
   float tex_offset_y = tile_rect.y() % checkerboard_width;
-  float tex_scale_x = tile_rect.width();
-  float tex_scale_y = tile_rect.height();
+  float tex_scale_x = tile_rect.width() / quad->scale;
+  float tex_scale_y = tile_rect.height() / quad->scale;
   GLC(gl_,
       gl_->Uniform4f(program->fragment_shader().tex_transform_location(),
                      tex_offset_x,