[BUGFIX] InlineSettings broken if extJs not loaded

The pagerenderer can add javascript inline settings to the output.
This does not work if extJs is not loaded, because of missing
initialization of js object TYPO3.
This patch makes sure that TYPO3 object is iniitalized correctly,
if extJs is not loaded.

Change-Id: I2f9750cd0188cbbb042d02b6d3f5c6da2a544589
Fixes: #38879
Releases: 6.2, 6.1, 6.0
Reviewed-on: https://review.typo3.org/20392
Reviewed-by: Christian Kuhn
Tested-by: Christian Kuhn