Tests that console's copy command is copying into front-end buffer.

InspectorFrontendHost.copyText: 1
InspectorFrontendHost.copyText: Infinity
InspectorFrontendHost.copyText: NaN
InspectorFrontendHost.copyText: [object Object]
InspectorFrontendHost.copyText: false
InspectorFrontendHost.copyText: null
InspectorFrontendHost.copyText: null
InspectorFrontendHost.copyText: null
InspectorFrontendHost.copyText: qwerty
InspectorFrontendHost.copyText: true
InspectorFrontendHost.copyText: {
    "foo": "bar"
}
InspectorFrontendHost.copyText: undefined