From 8450c835d52db07c2a70cb5f4178af6fa8fcf9c9 Mon Sep 17 00:00:00 2001
From: Olli Pettay <Olli.Pettay@helsinki.fi>
Date: Wed, 1 May 2019 01:41:06 +0300
Subject: [PATCH] Bug 1548146 - Tweak sLastForgetSkippableCycleEndTime handling
 to be able to check two tasks within < 1ms, r=mccr8

--HG--
extra : rebase_source : a4d82ac6cbac8d58b091565cb8ccc4c12d71fcde
---
 dom/base/nsJSEnvironment.cpp | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/dom/base/nsJSEnvironment.cpp b/dom/base/nsJSEnvironment.cpp
index f7fb7b0613b0..a10eaf538056 100644
--- a/dom/base/nsJSEnvironment.cpp
+++ b/dom/base/nsJSEnvironment.cpp
@@ -2066,11 +2066,11 @@ void nsJSContext::MaybePokeCC() {
 
   // If GC hasn't run recently and forget skippable only cycle was run,
   // don't start a new cycle too soon.
-  if (sCleanupsSinceLastGC > NS_MAJOR_FORGET_SKIPPABLE_CALLS) {
+  if ((sCleanupsSinceLastGC > NS_MAJOR_FORGET_SKIPPABLE_CALLS) &&
+      !sLastForgetSkippableCycleEndTime.IsNull()) {
     uint32_t sinceLastForgetSkippableCycle =
         TimeUntilNow(sLastForgetSkippableCycleEndTime);
-    if (sinceLastForgetSkippableCycle &&
-        sinceLastForgetSkippableCycle <
+    if (sinceLastForgetSkippableCycle <
             NS_TIME_BETWEEN_FORGET_SKIPPABLE_CYCLES) {
       return;
     }