Bug 252836 Exception ``[Exception... "Component returned failure code: 0x80004005 (NS_ERROR_FAILURE) [nsIWebNavigation.sessionHistory]" nsresult: "0x80004005 (NS_ERROR_FAILURE)" location: "JS frame :: chrome://global/content/bindings/browser.xml :: onxbldestructor :: line 402" data: no]'' thrown from function onxbldestructor(event=Event:{0}) in <chrome://global/content/bindings/browser.xml> line 402.

r=neil sr=bz

browser/base/content/contentAreaUtils.js

@@ -649,7 +649,7 @@ function getPostData()
 {
   try {
     var sessionHistory = getWebNavigation().sessionHistory;
-    entry = sessionHistory.getEntryAtIndex(sessionHistory.index, false);
+    var entry = sessionHistory.getEntryAtIndex(sessionHistory.index, false);
     entry = entry.QueryInterface(Components.interfaces.nsISHEntry);
     return entry.postData;
   }

docshell/base/nsDocShell.cpp

@@ -2984,16 +2984,11 @@ NS_IMETHODIMP
 nsDocShell::GetSessionHistory(nsISHistory ** aSessionHistory)
 {
     NS_ENSURE_ARG_POINTER(aSessionHistory);
-    if (mSessionHistory) {
         *aSessionHistory = mSessionHistory;
         NS_IF_ADDREF(*aSessionHistory);
         return NS_OK;
     }
 
-    return NS_ERROR_FAILURE;
-
-}
-
 //*****************************************************************************
 // nsDocShell::nsIWebPageDescriptor
 //*****************************************************************************   

embedding/qa/jstests/sHistory/nsISHistoryTestLib.js

@@ -61,28 +61,28 @@ function sHistoryInit(theWindow)
     }
     catch(e){
        alert("Unable to get interface requestor object: " + e);
-       return false;
+       return null;
     }
     try {
        webNav = ifaceReq.getInterface(Components.interfaces.nsIWebNavigation);
     }
     catch(e) {
       alert("Unable to get WebNavigation: " + e);
-      return false;
+      return null;
     }               
     try {
        sHistory = webNav.sessionHistory;
     }
     catch(e) {
       alert("Didn't get SessionHistory object: " + e);
-      return false;
+      return null;
     } 
     return sHistory;
   }
   catch(e) 
   {
     alert("Could not find Session History component: " + e);
-    return false;
+    return null;
   }
 }
 
@@ -93,7 +93,7 @@ function testHistoryCount(sHistory)
 {
   if (!sHistory) {
     alert("Didn't get SessionHistory object");
-    return false;  
+    return 0;
   }
   var cnt = sHistory.count;     // GetCount() 
   return cnt; 
@@ -101,13 +101,14 @@ function testHistoryCount(sHistory)
 
 // *************************************************************************
 // testHistoryIndex() returns the current session history index.
+// returns negative one if the history object is null.
 // It accepts the session history object as the input parameter.
 // In your test script, 
 function testHistoryIndex(sHistory)
 {
   if (!sHistory) {
     alert("Didn't get SessionHistory object");
-    return false;  
+    return -1;
   }
   var shIndex = sHistory.index;   // GetIndex()
   return shIndex;
@@ -120,7 +121,7 @@ function testMaxLength(sHistory)
 {
   if (!sHistory) {
     alert("Didn't get SessionHistory object");
-    return false;  
+    return 0;
   }
   var maxLen = sHistory.maxLength;  // GetMaxLength
   return maxLen;
@@ -136,7 +137,7 @@ function testGetEntryAtIndex(sHistory, cnt, modIndex)
 {
   if (!sHistory) {
     alert("Didn't get SessionHistory object");
-    return false;  
+    return null;
   }
   var entry = sHistory.getEntryAtIndex(cnt, modIndex);
 
@@ -150,7 +151,7 @@ function  testSimpleEnum(sHistory)
 {
   if (!sHistory) {
     alert("Didn't get SessionHistory object");
-    return false;  
+    return null;
   }
    var simpleEnum = sHistory.SHistoryEnumerator;
    
@@ -189,7 +190,7 @@ function  testHistoryEntryUri(nextHE, index)
 {
   if (!nextHE) {
     alert("Didn't get history entry object");
-    return false;  
+    return null;
   }
    // Get URI for the  next Entry
    Uri = entry.URI;
@@ -206,7 +207,7 @@ function  testHistoryEntryTitle(nextHE, index)
 {
   if (!nextHE) {
     alert("Didn't get history entry object");
-    return false;  
+    return null;
   }
    // Get Title for the nextEntry
    title = entry.title;
@@ -222,7 +223,7 @@ function  testHistoryEntryFrame(nextHE, index)
 {
   if (!nextHE) {
     alert("Didn't get history entry object");
-    return false;  
+    return null;
   }
   // Get SubFrame Status for the nextEntry
    frameStatus = entry.isSubFrame;

embedding/qa/jstests/webNav/nsIWebNavTestLib.js

@@ -275,7 +275,7 @@ function testSessionHistory(webNav)
 {
   if (!webNav) {
     alert("Didn't get web navigation object");
-    return false;
+    return null;
   }
    // Get the session history 
   getSHistory = webNav.sessionHistory; 

xpfe/browser/resources/content/navigator.js

@@ -516,14 +516,7 @@ function Startup()
 
   //initConsoleListener();
 
-  // XXXjag work-around for bug 113076
-  // there's another bug where we throw an exception when getting
-  // sessionHistory if it is null, which I'm exploiting here to
-  // detect the situation described in bug 113076.
-  // The same problem caused bug 139522, also worked around below.
-  try {
-    getBrowser().sessionHistory;
-  } catch (e) {
+  if (!getBrowser().sessionHistory) {
     /* Session history might not be available,
        so we wrap access to it in a try block */
     try {