Merge SVGSMILElement's BeginListChanged and EndListChanged

Merge these two functions into one - InstanceListChanged - taking the
list that changed as an argument. This is preparation for unifying this
code-path with the other interval resolving code-path.

Bug: 998526
Change-Id: I3727a5dfe76236bac7b6283a48d334426093d2ae
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1827278Reviewed-by: Stephen Chenney <schenney@chromium.org>
Commit-Queue: Fredrik Söderquist <fs@opera.com>
Cr-Commit-Position: refs/heads/master@{#700270}

third_party/blink/renderer/core/svg/animation/svg_smil_element.cc

@@ -515,7 +515,7 @@ void SVGSMILElement::ParseAttribute(const AttributeModificationParams& params) {
     ParseBeginOrEnd(value.GetString(), kBegin);
     if (isConnected()) {
       ConnectConditions();
-      BeginListChanged(Elapsed());
+      InstanceListChanged(kBegin, Elapsed());
       if (time_container_)
         time_container_->NotifyIntervalsChanged();
     }
@@ -528,7 +528,7 @@ void SVGSMILElement::ParseAttribute(const AttributeModificationParams& params) {
     ParseBeginOrEnd(value.GetString(), kEnd);
     if (isConnected()) {
       ConnectConditions();
-      EndListChanged(Elapsed());
+      InstanceListChanged(kEnd, Elapsed());
       if (time_container_)
         time_container_->NotifyIntervalsChanged();
     }
@@ -735,11 +735,8 @@ void SVGSMILElement::AddInstanceTime(BeginOrEnd begin_or_end,
   Vector<SMILTimeWithOrigin>& list =
       begin_or_end == kBegin ? begin_times_ : end_times_;
   InsertSortedAndUnique(list, SMILTimeWithOrigin(time, origin));
-  if (begin_or_end == kBegin)
-    BeginListChanged(current_presentation_time);
-  else
-    EndListChanged(current_presentation_time);
 
+  InstanceListChanged(begin_or_end, current_presentation_time);
   if (time_container_)
     time_container_->NotifyIntervalsChanged();
 }
@@ -873,11 +870,27 @@ SMILTime SVGSMILElement::NextInterestingTime(SMILTime presentation_time) const {
                   FindInstanceTime(kBegin, presentation_time, false));
 }
 
-void SVGSMILElement::BeginListChanged(SMILTime event_time) {
+void SVGSMILElement::InstanceListChanged(BeginOrEnd begin_or_end,
+                                         SMILTime event_time) {
   if (is_waiting_for_first_interval_) {
     ResolveFirstInterval();
     return;
   }
+  if (begin_or_end == kEnd) {
+    // If we have no current interval, or the current interval ends before the
+    // indicated time, then a new 'end' instance time will have no effect.
+    if (!interval_.IsResolved() || interval_.EndsBefore(event_time))
+      return;
+    SMILTime new_end = FindInstanceTime(kEnd, interval_.begin, false);
+    if (interval_.EndsBefore(new_end))
+      return;
+    new_end = ResolveActiveEnd(interval_.begin, new_end);
+    if (new_end != interval_.end) {
+      interval_.end = new_end;
+      NotifyDependentsOnNewInterval(interval_);
+    }
+    return;
+  }
   // Never resolve more than one interval when restart is 'never'.
   if (GetRestart() == kRestartNever)
     return;
@@ -903,25 +916,6 @@ void SVGSMILElement::BeginListChanged(SMILTime event_time) {
   }
 }
 
-void SVGSMILElement::EndListChanged(SMILTime event_time) {
-  if (is_waiting_for_first_interval_) {
-    ResolveFirstInterval();
-    return;
-  }
-  // If we have no current interval, or the current interval ends before the
-  // indicated time, then a new 'end' instance time will have no effect.
-  if (!interval_.IsResolved() || interval_.EndsBefore(event_time))
-    return;
-  SMILTime new_end = FindInstanceTime(kEnd, interval_.begin, false);
-  if (interval_.EndsBefore(new_end))
-    return;
-  new_end = ResolveActiveEnd(interval_.begin, new_end);
-  if (new_end != interval_.end) {
-    interval_.end = new_end;
-    NotifyDependentsOnNewInterval(interval_);
-  }
-}
-
 void SVGSMILElement::CheckAndUpdateInterval(SMILTime elapsed) {
   DCHECK(!is_waiting_for_first_interval_);
   DCHECK(interval_.BeginsBefore(elapsed));

third_party/blink/renderer/core/svg/animation/svg_smil_element.h

@@ -183,8 +183,7 @@ class CORE_EXPORT SVGSMILElement : public SVGElement, public SVGTests {
   SMILTime RepeatingDuration() const;
   const SMILInterval& GetActiveInterval(SMILTime elapsed) const;
 
-  void BeginListChanged(SMILTime event_time);
-  void EndListChanged(SMILTime event_time);
+  void InstanceListChanged(BeginOrEnd, SMILTime event_time);
 
   // This represents conditions on elements begin or end list that need to be
   // resolved on runtime, for example