Bug 755508: Do not allow the use of NaN dates as keys. r=sicking

dom/indexedDB/Key.cpp

@@ -168,6 +168,9 @@ Key::EncodeJSValInternal(JSContext* aCx, const jsval aVal,
     }
 
     if (JS_ObjectIsDate(aCx, obj)) {
+      if (!js_DateIsValid(aCx, obj))  {
+        return NS_ERROR_DOM_INDEXEDDB_DATA_ERR;
+      }
       EncodeNumber(js_DateGetMsecSinceEpoch(aCx, obj), eDate + aTypeOffset);
       return NS_OK;
     }

dom/indexedDB/test/unit/test_keys.js

@@ -211,11 +211,14 @@ function testSteps()
     null,
     /x/,
     {},
+    new Date(NaN),
+    new Date("foopy"),
     [nan],
     [undefined],
     [null],
     [/x/],
     [{}],
+    [new Date(NaN)],
     [1, nan],
     [1, undefined],
     [1, null],