Web Inspector: move showWhitespace option into experiments

Web Inspector: move showWhitespace option into experiments
https://bugs.webkit.org/show_bug.cgi?id=109552

Patch by Andrey Lushnikov <lushnikov@chromium.org> on 2013-02-12
Reviewed by Vsevolod Vlasov.

Source/WebCore:

Remove "show whitespace" setting and add it to experiments.

No new tests: fixed an existing test to verify changes.

* English.lproj/localizedStrings.js:
* inspector/front-end/DefaultTextEditor.js:
(WebInspector.TextEditorMainPanel):
(WebInspector.TextEditorMainPanel.prototype.wasShown):
(WebInspector.TextEditorMainPanel.prototype.willHide):
* inspector/front-end/Settings.js:
(WebInspector.ExperimentsSettings):
* inspector/front-end/SettingsScreen.js:
(WebInspector.GenericSettingsTab):

LayoutTests:

Fix layout test to switch on experiment instead of toggling one of the
options.

* inspector/editor/text-editor-show-whitespace-expected.txt:
* inspector/editor/text-editor-show-whitespace.html:

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@142597 268f45cc-cd09-0410-ab3c-d52691b4dbfc