[v8] Fix: Fancy Button Content Fitting

[bbazukun123]

• Reset text/icon view scaling back to the default scale before doing the fitToView call to prevent the persistent of scale < 1 from the initial fitting.
  eg. if the button default view texture has a width of 150 and the content text has a width of 200, it will apply 0.75 scaling to the text view to fit it within the button (assuming that the padding is 0). Then if the button width is then set to 250, the text will still remain at 0.75 despite that it no longer needed to be scaled down to fit within the button.
• A ignoreRefitting is provided in case the persistent scaling behaviour from before is preferred.
• Add the ability to pass in the base scale for text and icon at instantiation. This will be prioritise over the automatic extraction from the new text or icon views.
• Add the ability to disable uniform scaling on the fitToView function to allow the child to maintain its aspect ratio from before the fitting.