Bug 579535 - Remove AddScriptBlockerAndPreventAddingRunners() API and warn about script runner failures. r=bz

content/base/public/nsContentUtils.h

@@ -1451,13 +1451,6 @@ public:
    */
   static void AddScriptBlocker();
 
-  /**
-   * Increases the count of blockers preventing scripts from running.
-   * Also, while this script blocker is active, script runners must not be
-   * added --- we'll assert if one is, and ignore it.
-   */
-  static void AddScriptBlockerAndPreventAddingRunners();
-
   /**
    * Decreases the count of blockers preventing scripts from running.
    * NOTE: You might want to use nsAutoScriptBlocker rather than calling

content/base/src/nsContentUtils.cpp

@@ -260,7 +260,6 @@ PRUint32 nsContentUtils::sDOMNodeRemovedSuppressCount = 0;
 #endif
 nsTArray< nsCOMPtr<nsIRunnable> >* nsContentUtils::sBlockedScriptRunners = nsnull;
 PRUint32 nsContentUtils::sRunnersCountAtFirstBlocker = 0;
-PRUint32 nsContentUtils::sScriptBlockerCountWhereRunnersPrevented = 0;
 nsIInterfaceRequestor* nsContentUtils::sSameOriginChecker = nsnull;
 
 bool nsContentUtils::sIsHandlingKeyBoardEvent = false;
@@ -4417,25 +4416,12 @@ nsContentUtils::AddScriptBlocker()
   ++sScriptBlockerCount;
 }
 
-/* static */
-void
-nsContentUtils::AddScriptBlockerAndPreventAddingRunners()
-{
-  AddScriptBlocker();
-  if (sScriptBlockerCountWhereRunnersPrevented == 0) {
-    sScriptBlockerCountWhereRunnersPrevented = sScriptBlockerCount;
-  }
-}
-
 /* static */
 void
 nsContentUtils::RemoveScriptBlocker()
 {
   NS_ASSERTION(sScriptBlockerCount != 0, "Negative script blockers");
   --sScriptBlockerCount;
-  if (sScriptBlockerCount < sScriptBlockerCountWhereRunnersPrevented) {
-    sScriptBlockerCountWhereRunnersPrevented = 0;
-  }
   if (sScriptBlockerCount) {
     return;
   }
@@ -4469,10 +4455,6 @@ nsContentUtils::AddScriptRunner(nsIRunnable* aRunnable)
   }
 
   if (sScriptBlockerCount) {
-    if (sScriptBlockerCountWhereRunnersPrevented > 0) {
-      NS_ERROR("Adding a script runner when that is prevented!");
-      return false;
-    }
     return sBlockedScriptRunners->AppendElement(aRunnable) != nsnull;
   }
   

content/base/src/nsDocument.cpp

@@ -7097,8 +7097,16 @@ nsDocument::BlockOnload()
       // block onload only when there are no script blockers.
       ++mAsyncOnloadBlockCount;
       if (mAsyncOnloadBlockCount == 1) {
-        nsContentUtils::AddScriptRunner(
+        bool success = nsContentUtils::AddScriptRunner(
           NS_NewRunnableMethod(this, &nsDocument::AsyncBlockOnload));
+
+        // The script runner shouldn't fail to add. But if somebody broke
+        // something and it does, we'll thrash at 100% cpu forever. The best
+        // response is just to ignore the onload blocking request. See bug 579535.
+        if (!success) {
+          NS_WARNING("Disaster! Onload blocking script runner failed to add - expect bad things!");
+          mAsyncOnloadBlockCount = 0;
+        }
       }
       return;
     }