Bug #305017 --> myspell object gets leaked by mozMySpell

r=mvl
sr=bienvenu

extensions/spellcheck/myspell/src/mozMySpell.cpp

@@ -78,11 +78,13 @@ NS_IMPL_ISUPPORTS1(mozMySpell, mozISpellCheckingEngine)
 
 mozMySpell::mozMySpell()
 {
+  mMySpell = NULL;
 }
 
 mozMySpell::~mozMySpell()
 {
   mPersonalDictionary = nsnull;
+  delete mMySpell;
 }
 
 /* attribute wstring dictionary; */
@@ -134,6 +136,11 @@ NS_IMETHODIMP mozMySpell::SetDictionary(const PRUnichar *aDictionary)
     NS_ENSURE_SUCCESS(rv, rv);
     file->GetPath(dictFileName);
 
+    // SetDictionary can be called multiple times, so we might have a valid mMySpell instance 
+    // which needs cleaned up.
+    if (mMySpell)
+      delete mMySpell;
+
     mMySpell = new MySpell(NS_ConvertUTF16toUTF8(affFileName).get(), NS_ConvertUTF16toUTF8(dictFileName).get());
     if (!mMySpell)
       return NS_ERROR_FAILURE;

extensions/spellcheck/myspell/src/myspell.cpp

@@ -35,15 +35,13 @@ MySpell::MySpell(const char * affpath, const char * dpath)
 
 MySpell::~MySpell()
 {
-    if (pSMgr) delete pSMgr;
-    if (pAMgr) delete pAMgr;
-    if (pHMgr) delete pHMgr;
-    pSMgr = NULL;
-    pAMgr = NULL;
-    pHMgr = NULL;
+    delete pSMgr;
+    delete pAMgr;
+    delete pHMgr;
+    
     csconv= NULL;
-    if (encoding) free(encoding);
-    encoding = NULL;
+    if (encoding) 
+        free(encoding);
 }