[SVG] call GCController.collectAll on SVG leak tests to address Oilpan flakiness.

After r169941, the SVG leak tests reports failures, but delta is <0, so number of live nodes is not increasing. This CL loosen the check.

Also removes FIXME comments in the tests.

BUG=340522
NOTRY=true

Review URL: https://codereview.chromium.org/211933007

git-svn-id: svn://svn.chromium.org/blink/trunk@170010 bbb929c8-8fbe-4397-9dbb-9b2b20218538

third_party/WebKit/LayoutTests/svg/animations/smil-leak-element-instances-noBaseValRef.svg

@@ -34,17 +34,15 @@ function createAnimatedRectInstance() {
 
 function cleanup() {
     // Collect garbage before recording starting live node count, in case there are live elements from previous tests.
-    // FIXME: Unclear why two calls to collect() are required, see crbug.com/307614
-    GCController.collect();
-    GCController.collect();
+    GCController.collectAll();
     var originalLiveElements = internals.numberOfLiveNodes();
 
     while (g.hasChildNodes())
         g.removeChild(g.lastChild);
 
-    GCController.collect();
+    GCController.collectAll();
 
-    // FIXME: Why 400 and not 200?
+    // This is 400 instead of 200 as it creates shadow tree elements.
     var liveDelta = originalLiveElements - internals.numberOfLiveNodes() - 400;
     if (liveDelta == 0)
         log("PASS");

third_party/WebKit/LayoutTests/svg/animations/smil-leak-element-instances.svg

@@ -34,17 +34,15 @@ function createAnimatedRectInstance() {
 
 function cleanup() {
     // Collect garbage before recording starting live node count, in case there are live elements from previous tests.
-    // FIXME: Unclear why two calls to collect() are required, see crbug.com/307614
-    GCController.collect();
-    GCController.collect();
+    GCController.collectAll();
     var originalLiveElements = internals.numberOfLiveNodes();
 
     while (g.hasChildNodes())
         g.removeChild(g.lastChild);
 
-    GCController.collect();
+    GCController.collectAll();
 
-    // FIXME: Why is this 400 instead of 200?
+    // This is 400 instead of 200 as it creates shadow tree elements.
     var liveDelta = originalLiveElements - internals.numberOfLiveNodes() - 400;
     if (liveDelta == 0)
         log("PASS");

third_party/WebKit/LayoutTests/svg/animations/smil-leak-elements.svg

@@ -32,15 +32,13 @@ function createAnimatedRect() {
 
 function cleanup() {
     // Collect garbage before recording starting live node count, in case there are live elements from previous tests.
-    // FIXME: Unclear why two calls to collect() are required, see crbug.com/307614
-    GCController.collect();
-    GCController.collect();
+    GCController.collectAll();
     var originalLiveElements = internals.numberOfLiveNodes();
 
     while (g.hasChildNodes())
         g.removeChild(g.lastChild);
 
-    GCController.collect();
+    GCController.collectAll();
 
     var liveDelta = originalLiveElements - internals.numberOfLiveNodes() - 200;
     if (liveDelta == 0)