Bug 910230 - Intermittent tests/test-panel.test Parent Resize Hack | Test output exceeded timeout (300s)

- Removed dependency from timeout
- Removed code relative to bug 635673
Merge pull request #1230 from ZER0/panel-resize-test/910230

Bug 910230 - Intermittent tests/test-panel.test Parent Resize Hack | Test output exceeded timeout (300s) r=@Mossop