Bug 678938 - SMIL: Make sure current interval is properly cleared when doing a rewind; r=dholbert

content/smil/crashtests/678938-1.svg

@@ -0,0 +1,11 @@
+<svg xmlns="http://www.w3.org/2000/svg" class="reftest-wait">
+<script>
+  window.addEventListener("load", function() {
+    setTimeout(function() {
+      document.documentElement.setCurrentTime(0);
+      document.documentElement.removeAttribute("class");
+    }, 0);
+  }, false);
+</script>
+<set id="c"/><set id="b" begin="c.begin; b.begin"/>
+</svg>

content/smil/crashtests/crashtests.list

@@ -37,7 +37,8 @@ load 615872-1.svg
 load 650732-1.svg
 load 665334-1.svg
 load 669225-1.svg
-load 670313-1.svg
 load 669225-2.svg
+load 670313-1.svg
 load 678822-1.svg
 load 678847-1.svg
+load 678938-1.svg

content/smil/nsSMILTimedElement.cpp

@@ -758,10 +758,10 @@ nsSMILTimedElement::Rewind()
                     mSeekState == SEEK_BACKWARD_FROM_ACTIVE,
                     "Rewind in the middle of a forwards seek?");
 
-  ClearIntervals();
-  // ClearIntervals puts us in to the POSTACTIVE state but we're doing a full
-  // rewind so go back to the startup state
+  // Putting us in the startup state will ensure we skip doing any interval
+  // updates
   mElementState = STATE_STARTUP;
+  ClearIntervals();
 
   UnsetBeginSpec(RemoveNonDynamic);
   UnsetEndSpec(RemoveNonDynamic);
@@ -784,6 +784,8 @@ nsSMILTimedElement::Rewind()
 
   mPrevRegisteredMilestone = sMaxMilestone;
   RegisterMilestone();
+  NS_ABORT_IF_FALSE(!mCurrentInterval,
+                    "Current interval is set at end of rewind");
 }
 
 namespace
@@ -1332,7 +1334,9 @@ nsSMILTimedElement::ClearSpecs(TimeValueSpecList& aSpecs,
 void
 nsSMILTimedElement::ClearIntervals()
 {
-  mElementState = STATE_POSTACTIVE;
+  if (mElementState != STATE_STARTUP) {
+    mElementState = STATE_POSTACTIVE;
+  }
   mCurrentRepeatIteration = 0;
   ResetCurrentInterval();