5 files changed, 18 insertions, 78 deletions

diff --git a/dom/base/CustomElementRegistry.cpp b/dom/base/CustomElementRegistry.cpp
index 2d7907bd7..ab1e60366 100644
--- a/dom/base/CustomElementRegistry.cpp
+++ b/dom/base/CustomElementRegistry.cpp
@@ -6,6 +6,7 @@
 
 #include "mozilla/dom/CustomElementRegistry.h"
 
+#include "mozilla/CycleCollectedJSContext.h"
 #include "mozilla/dom/CustomElementRegistryBinding.h"
 #include "mozilla/dom/HTMLElementBinding.h"
 #include "mozilla/dom/WebComponentsBinding.h"
diff --git a/dom/base/nsContentUtils.cpp b/dom/base/nsContentUtils.cpp
index 87c879746..402dfd1c5 100644
--- a/dom/base/nsContentUtils.cpp
+++ b/dom/base/nsContentUtils.cpp
@@ -259,7 +259,6 @@ nsIWordBreaker *nsContentUtils::sWordBreaker;
 nsIBidiKeyboard *nsContentUtils::sBidiKeyboard = nullptr;
 uint32_t nsContentUtils::sScriptBlockerCount = 0;
 uint32_t nsContentUtils::sDOMNodeRemovedSuppressCount = 0;
-uint32_t nsContentUtils::sMicroTaskLevel = 0;
 AutoTArray<nsCOMPtr<nsIRunnable>, 8>* nsContentUtils::sBlockedScriptRunners = nullptr;
 uint32_t nsContentUtils::sRunnersCountAtFirstBlocker = 0;
 nsIInterfaceRequestor* nsContentUtils::sSameOriginChecker = nullptr;
@@ -5302,51 +5301,6 @@ nsContentUtils::RunInMetastableState(already_AddRefed<nsIRunnable> aRunnable)
   CycleCollectedJSContext::Get()->RunInMetastableState(Move(aRunnable));
 }
 
-void
-nsContentUtils::EnterMicroTask()
-{
-  MOZ_ASSERT(NS_IsMainThread());
-  ++sMicroTaskLevel;
-}
-
-void
-nsContentUtils::LeaveMicroTask()
-{
-  MOZ_ASSERT(NS_IsMainThread());
-  if (--sMicroTaskLevel == 0) {
-    PerformMainThreadMicroTaskCheckpoint();
-  }
-}
-
-bool
-nsContentUtils::IsInMicroTask()
-{
-  MOZ_ASSERT(NS_IsMainThread());
-  return sMicroTaskLevel != 0;
-}
-
-uint32_t
-nsContentUtils::MicroTaskLevel()
-{
-  MOZ_ASSERT(NS_IsMainThread());
-  return sMicroTaskLevel;
-}
-
-void
-nsContentUtils::SetMicroTaskLevel(uint32_t aLevel)
-{
-  MOZ_ASSERT(NS_IsMainThread());
-  sMicroTaskLevel = aLevel;
-}
-
-void
-nsContentUtils::PerformMainThreadMicroTaskCheckpoint()
-{
-  MOZ_ASSERT(NS_IsMainThread());
-
-  nsDOMMutationObserver::HandleMutations();
-}
-
 /*
  * Helper function for nsContentUtils::ProcessViewportInfo.
  *
diff --git a/dom/base/nsContentUtils.h b/dom/base/nsContentUtils.h
index 19b007591..4200a0621 100644
--- a/dom/base/nsContentUtils.h
+++ b/dom/base/nsContentUtils.h
@@ -1740,17 +1740,6 @@ public:
    */
   static void RunInMetastableState(already_AddRefed<nsIRunnable> aRunnable);
 
-  // Call EnterMicroTask when you're entering JS execution.
-  // Usually the best way to do this is to use nsAutoMicroTask.
-  static void EnterMicroTask();
-  static void LeaveMicroTask();
-
-  static bool IsInMicroTask();
-  static uint32_t MicroTaskLevel();
-  static void SetMicroTaskLevel(uint32_t aLevel);
-
-  static void PerformMainThreadMicroTaskCheckpoint();
-
   /* Process viewport META data. This gives us information for the scale
    * and zoom of a page on mobile devices. We stick the information in
    * the document header and use it later on after rendering.
@@ -2850,7 +2839,6 @@ private:
   static bool sInitialized;
   static uint32_t sScriptBlockerCount;
   static uint32_t sDOMNodeRemovedSuppressCount;
-  static uint32_t sMicroTaskLevel;
   // Not an nsCOMArray because removing elements from those is slower
   static AutoTArray<nsCOMPtr<nsIRunnable>, 8>* sBlockedScriptRunners;
   static uint32_t sRunnersCountAtFirstBlocker;
@@ -2928,19 +2916,6 @@ public:
   }
 };
 
-class MOZ_STACK_CLASS nsAutoMicroTask
-{
-public:
-  nsAutoMicroTask()
-  {
-    nsContentUtils::EnterMicroTask();
-  }
-  ~nsAutoMicroTask()
-  {
-    nsContentUtils::LeaveMicroTask();
-  }
-};
-
 namespace mozilla {
 namespace dom {
 
diff --git a/dom/base/nsDocument.cpp b/dom/base/nsDocument.cpp
index f3e492589..293e48eb0 100644
--- a/dom/base/nsDocument.cpp
+++ b/dom/base/nsDocument.cpp
@@ -12610,8 +12610,12 @@ MarkDocumentTreeToBeInSyncOperation(nsIDocument* aDoc, void* aData)
 
 nsAutoSyncOperation::nsAutoSyncOperation(nsIDocument* aDoc)
 {
-  mMicroTaskLevel = nsContentUtils::MicroTaskLevel();
-  nsContentUtils::SetMicroTaskLevel(0);
+  mMicroTaskLevel = 0;
+  CycleCollectedJSContext* ccjs = CycleCollectedJSContext::Get();
+  if (ccjs) {
+    mMicroTaskLevel = ccjs->MicroTaskLevel();
+    ccjs->SetMicroTaskLevel(0);
+  }
   if (aDoc) {
     if (nsPIDOMWindowOuter* win = aDoc->GetWindow()) {
       if (nsCOMPtr<nsPIDOMWindowOuter> top = win->GetTop()) {
@@ -12627,7 +12631,10 @@ nsAutoSyncOperation::~nsAutoSyncOperation()
   for (int32_t i = 0; i < mDocuments.Count(); ++i) {
     mDocuments[i]->SetIsInSyncOperation(false);
   }
-  nsContentUtils::SetMicroTaskLevel(mMicroTaskLevel);
+  CycleCollectedJSContext* ccjs = CycleCollectedJSContext::Get();
+  if (ccjs) {
+    ccjs->SetMicroTaskLevel(mMicroTaskLevel);
+  }
 }
 
 gfxUserFontSet*
diff --git a/dom/base/nsJSUtils.cpp b/dom/base/nsJSUtils.cpp
index 98b367b66..b6c843065 100644
--- a/dom/base/nsJSUtils.cpp
+++ b/dom/base/nsJSUtils.cpp
@@ -25,7 +25,7 @@
 #include "xpcpublic.h"
 #include "nsContentUtils.h"
 #include "nsGlobalWindow.h"
-
+#include "mozilla/CycleCollectedJSContext.h"
 #include "mozilla/dom/BindingUtils.h"
 #include "mozilla/dom/Date.h"
 #include "mozilla/dom/Element.h"
@@ -159,7 +159,8 @@ nsJSUtils::EvaluateString(JSContext* aCx,
              aEvaluationGlobal);
   MOZ_ASSERT_IF(aOffThreadToken, aCompileOptions.noScriptRval);
   MOZ_ASSERT(NS_IsMainThread());
-  MOZ_ASSERT(nsContentUtils::IsInMicroTask());
+  MOZ_ASSERT(CycleCollectedJSContext::Get() &&
+             CycleCollectedJSContext::Get()->MicroTaskLevel());
 
   // Unfortunately, the JS engine actually compiles scripts with a return value
   // in a different, less efficient way.  Furthermore, it can't JIT them in many
@@ -293,7 +294,8 @@ nsJSUtils::CompileModule(JSContext* aCx,
              aEvaluationGlobal);
   MOZ_ASSERT(JS::CurrentGlobalOrNull(aCx) == aEvaluationGlobal);
   MOZ_ASSERT(NS_IsMainThread());
-  MOZ_ASSERT(nsContentUtils::IsInMicroTask());
+  MOZ_ASSERT(CycleCollectedJSContext::Get() &&
+             CycleCollectedJSContext::Get()->MicroTaskLevel());
 
   NS_ENSURE_TRUE(xpc::Scriptability::Get(aEvaluationGlobal).Allowed(), NS_OK);
 
@@ -330,7 +332,8 @@ nsJSUtils::ModuleEvaluation(JSContext* aCx, JS::Handle<JSObject*> aModule)
 
   MOZ_ASSERT(aCx == nsContentUtils::GetCurrentJSContext());
   MOZ_ASSERT(NS_IsMainThread());
-  MOZ_ASSERT(nsContentUtils::IsInMicroTask());
+  MOZ_ASSERT(CycleCollectedJSContext::Get() &&
+             CycleCollectedJSContext::Get()->MicroTaskLevel());
 
   NS_ENSURE_TRUE(xpc::Scriptability::Get(aModule).Allowed(), NS_OK);