Fix ScaleStore tests.

Be more dynamic when checking whether certain expected handlers are bound. We
cannot assume that no previous handlers are being bound e.g. by some internal
OpenLayers logic. In this case our map might have some handlers at unexpected
indices, because its TileManager instance registered events previously.
List and run Symbolizer tests only once.
Fix slider/Zoom test through delaying checks.
Fix selection/FeatureModel test through delaying checks.
Fix plugins/PrintProviderField tests.

Instead of mocking up an `ownerCt` with a plain object, actually instanciate a
panel and set it as `ownerCt`.
Fix PrintMapPanel test by using store methods.
Fix the grid/column/Symbolizer tests.

OpenLayers no longer uses dots in the ids it generates for markup.
Let FeatureStore::loadRawData fire a load event.

The method `loadRawData` of the FeatureStore would throw a `load`-
event in Ext 4.1.3, while version 4.2.1 removes this behaviour.

We therefore overwrite loadRawData and again throw the event just
as Ext did previously.

See also the APIdocs and the links mentioned there.
Let LayerStore::loadRawData fire a load event.

The method `loadRawData` of the LayerStore would throw a `load`-
event in Ext 4.1.3, while version 4.2.1 removes this behaviour.

We therefore overwrite loadRawData and again throw the event just
as Ext did previously.

See also the APIdocs and the links mentioned there.
Fix the FeatureStore tests.

Ext JS 4.2.1 introduced an own private method `onUpdate`. That was called before
our bound method would be fired as listener to the 'update' event. This commit
fixes this odd behaviour by renaming our own method to `onStoreUpdate`.

Compare the rendered source of the relevant code here:

  * ExtJS 4.2.1: `afterEdit` calls `onUpdate` and then fires `update`:
    http://docs-origin.sencha.com/extjs/4.2.1/source/AbstractStore.html#Ext-data-AbstractStore-method-afterEdit
  * ExtJS 4.1.3: `afterEdit` doesn't call `onUpdate`, but only fires `update`:
    http://docs-origin.sencha.com/extjs/4.1.3/source/AbstractStore.html#Ext-data-AbstractStore-method-afterEdit
Fix the LayerStore tests.

As the method Ext.data.Store::remove has changed internally between
versions 4.2.1 and 4.1.3, we need to guard when a record is being removed
from a layer store, that wasn't previously in the store.

Compare the different internal code with the following links:

  * ExtJS 4.2.1: `records.isModel` is called without checking whether `records`
    is `undefined`:
    http://docs-origin.sencha.com/extjs/4.2.1/source/Store.html#Ext-data-Store-method-remove
  * ExtJS 4.1.3: In the case that `records` is passed as `undefined`, the
    method does not throw an exception:
    http://docs-origin.sencha.com/extjs/4.1.3/source/Store.html#Ext-data-Store-method-remove
Rename private handler and unbind it on destroy.