exo: Allow updating cc::Surface viewport and crop state independently.

components/exo/surface.cc

Index: components/exo/surface.cc
diff --git a/components/exo/surface.cc b/components/exo/surface.cc
index 08b8a187655d5653b73feec064e77f19ba1b565a..8e613846093ab1cfc3f23d648473da5ac738353e 100644
--- a/components/exo/surface.cc
+++ b/components/exo/surface.cc
@@ -388,13 +388,21 @@ void Surface::PlaceSubSurfaceBelow(Surface* sub_surface, Surface* sibling) {
 void Surface::SetViewport(const gfx::Size& viewport) {
   TRACE_EVENT1("exo", "Surface::SetViewport", "viewport", viewport.ToString());
 
+  if (pending_viewport_ == viewport)
+    return;
+
   pending_viewport_ = viewport;
+  changed_viewport_or_crop_ = true;
 }
 
 void Surface::SetCrop(const gfx::RectF& crop) {
   TRACE_EVENT1("exo", "Surface::SetCrop", "crop", crop.ToString());
 
+  if (pending_crop_ == crop)
+    return;
+
   pending_crop_ = crop;
+  changed_viewport_or_crop_ = true;
 }
 
 void Surface::SetOnlyVisibleOnSecureOutput(bool only_visible_on_secure_output) {
@@ -512,10 +520,13 @@ void Surface::CommitLayerContents() {
 void Surface::CommitSurfaceContents() {
   // We update contents if Attach() has been called since last commit.
   if (has_pending_contents_) {
-    has_pending_contents_ = false;
-
     current_buffer_ = pending_buffer_;
     pending_buffer_.reset();
+  }
+
+  if (has_pending_contents_ || changed_viewport_or_crop_) {
+    has_pending_contents_ = false;
+    changed_viewport_or_crop_ = false;
 
     bool secure_output_only = pending_only_visible_on_secure_output_;
     pending_only_visible_on_secure_output_ = false;