Null check after malloc in currently-unused osxspell component. b=283516 r=smorgan

extensions/spellcheck/osxspell/src/mozOSXSpell.mm

@@ -115,8 +115,9 @@ NS_IMETHODIMP mozOSXSpell::GetLanguage(PRUnichar **aLanguage)
     }
     mLanguage.Assign(*aLanguage);
   }
-  else
+  else {
     *aLanguage = ToNewUnicode(mLanguage);
+  }
 
   return *aLanguage ? NS_OK : NS_ERROR_OUT_OF_MEMORY;
 
@@ -299,6 +300,8 @@ NS_IMETHODIMP mozOSXSpell::Suggest(const PRUnichar *aWord, PRUnichar ***aSuggest
 
   PRUint32 length = [self length];
   PRUnichar* retStr = (PRUnichar*)nsMemory::Alloc((length + 1) * sizeof(PRUnichar));
+  if (!retStr)
+    return NULL;
   [self getCharacters:retStr];
   retStr[length] = PRUnichar(0);
   return retStr;