Kibana currently stores it's entire application state in the URL by rison encoding it and sticking it into a query string parameter, _a for AppState and _g for GlobalState.
This has functioned fine for a while, but Internet Explorer's short URL length restriction are starting to become a problem for more and more users. To provide these users with a workaround this adds an advanced config option that will store the state in sessionStorage instead of the URL.
This is accomplished by hashing the serialized version of the state, storing a short version of the hash in the URL, and storing the whole serialized state in sessionStorage using the hash + state-type as a key.
Since sessionStorage is limited in size, we must clean up old stored states after they become unreachable to the application. This is done using the new `LazyLruStore` class, a wrapper around sessionStorage. This wrapper helps us maintain the list of stored states based on the time they are accessed (On each set the access time is updates).
It's cleanup style is configured with it's maxItems, idealClearRatio, and maxIdealClearPercent configurations. The defaults for which should be sufficient.
`maxItems`: limits the store to n items, removing the oldest item when the list overflows
`idealClearRatio+maxIdealClearPercent`: when `store.setItem(key, value)` throws an error we try to clear space equal to `idealClearRatio * (key+value).length`, but no more space than `totalSize * maxIdealClearPercent`
The tests in master are currently failing regularly because our current browser tests are serious memory hogs. Investigation reveals that nearly every test is retaining all of the memory it causes to be allocated. We have made some progress to being able to diagnose the problems, but we expect that problem to take some serious work to fix. We need a short-term solution though, and this is it.
Rather than modify the bundling process, we will shard the top-level test suites by name. For now, we've created 4 shards, but adding new shards is trivial if we need to.
Sharding is accomplished by creating a murmur3 hash of the top level suite names, then bucketing based on the hash output. If a test suite resolves to shard2, but we are running shard1, we simply never pass the function to `mocha.describe()`. Rather than redefine every describe statement, we have shimmed the global `window.describe()` function to accomplish this.
- helper functions for dynamic css class names
- notifications: reposition the countdown button outside of the button group
- notifications/buttons: bootstrap primary/default button classes for custom actions
Several tests have been failing recently with "Error: Unexpected request: POST /api/kibana/settings/shortDots:enable, No more request expected" which seems to be caused by the field chooser tests calling `config.set('shortDots:enable', origValue)` in the test cleanup task. Rather than investigate it further I avoided the need to call `config.set()` by stubbing the `config.get()` method.
