Ensure Surface size always matches window size on swap

ui/compositor/compositor.cc

Index: ui/compositor/compositor.cc
diff --git a/ui/compositor/compositor.cc b/ui/compositor/compositor.cc
index bbf05bbbcd8ff03fd6e8f087f6359ba629a2e32e..981aef4cac7b9a96549957eeb59d18a3a04bebfd 100644
--- a/ui/compositor/compositor.cc
+++ b/ui/compositor/compositor.cc
@@ -256,8 +256,9 @@ void Compositor::ScheduleRedrawRect(const gfx::Rect& damage_rect) {
   host_->SetNeedsRedrawRect(damage_rect);
 }
 
-void Compositor::FinishAllRendering() {
+void Compositor::DisableSwapUntilResize() {
   host_->FinishAllRendering();
+  context_factory_->ResizeDisplay(this, gfx::Size());
 }
 
 void Compositor::SetLatencyInfo(const ui::LatencyInfo& latency_info) {
@@ -272,6 +273,7 @@ void Compositor::SetScaleAndSize(float scale, const gfx::Size& size_in_pixel) {
     size_ = size_in_pixel;
     host_->SetViewportSize(size_in_pixel);
     root_web_layer_->SetBounds(size_in_pixel);
+    context_factory_->ResizeDisplay(this, size_in_pixel);
   }
   if (device_scale_factor_ != scale) {
     device_scale_factor_ = scale;