Implements core logic for Pixel Canvas

ui/compositor/compositor.cc

Index: ui/compositor/compositor.cc
diff --git a/ui/compositor/compositor.cc b/ui/compositor/compositor.cc
index 353b9f9c161ef2220b1985f5f53881dbe85233d0..df21bf4eea7a1a00dfeb30212c4dc4694f7c15d2 100644
--- a/ui/compositor/compositor.cc
+++ b/ui/compositor/compositor.cc
@@ -323,6 +323,8 @@ void Compositor::SetScaleAndSize(float scale, const gfx::Size& size_in_pixel) {
   if (device_scale_factor_ != scale) {
     device_scale_factor_ = scale;
     host_->SetDeviceScaleFactor(scale);
+    if (IsPixelCanvasRecordingEnabled())

[danakj, 2017/07/21 17:29:39]

Can this be passed to the Constructor instead so unit tests can set it without
having to muck with trying to intercept command line?

[malaykeshav, 2017/07/21 23:30:17]

Done

+      host_->SetRecordingScaleFactor(scale);
     if (root_layer_)
       root_layer_->OnDeviceScaleFactorChanged(scale);
   }