Mozart: Ensure time always runs forward.

services/gfx/compositor/graph/scene_label.cc

Index: services/gfx/compositor/graph/scene_label.cc
diff --git a/services/gfx/compositor/graph/scene_label.cc b/services/gfx/compositor/graph/scene_label.cc
index b2955c589bc83d77b241eb066a304d0bfde260fb..a86222674b60c2318d7702a073a411b1824c6f26 100644
--- a/services/gfx/compositor/graph/scene_label.cc
+++ b/services/gfx/compositor/graph/scene_label.cc
@@ -22,18 +22,25 @@ std::string SceneLabel::FormattedLabel() const {
              : base::StringPrintf("<S%d:%s>", token_, label_.c_str());
 }
 
-std::string SceneLabel::FormattedLabelForVersion(uint32_t version) const {
-  return label_.empty() ? base::StringPrintf("<S%d/%d>", token_, version)
-                        : base::StringPrintf("<S%d:%s/%d>", token_,
-                                             label_.c_str(), version);
+std::string SceneLabel::FormattedLabelForVersion(
+    uint32_t version,
+    int64_t presentation_time) const {
+  return label_.empty()
+             ? base::StringPrintf("<S%d/v%d@%ld>", token_, version,
+                                  presentation_time)
+             : base::StringPrintf("<S%d:%s/v%d@%ld>", token_, label_.c_str(),
+                                  version, presentation_time);
 }
 
 std::string SceneLabel::FormattedLabelForNode(uint32_t version,
+                                              int64_t presentation_time,
                                               uint32_t node_id) const {
   return label_.empty()
-             ? base::StringPrintf("<S%d/%d>[%d]", token_, version, node_id)
-             : base::StringPrintf("<S%d:%s/%d>[%d]", token_, label_.c_str(),
-                                  version, node_id);
+             ? base::StringPrintf("<S%d/v%d@%ld>[#%d]", token_, version,
+                                  presentation_time, node_id)
+             : base::StringPrintf("<S%d:%s/v%d@%ld>[#%d]", token_,
+                                  label_.c_str(), version, presentation_time,
+                                  node_id);
 }
 
 }  // namespace compositor