JTabbedPane is not same in GTKLookAndFeel with different themes.

Step to reproduce:
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1) Run the attached program.
2) Select 'Scroll Tab Layout' radio button & select 'Top' Radio button.
3) Click on Launch -> Preferences -> Desktop Preferences ->Display -> Theme . You will see a frame with different themes.
4) select SmokeyBlue Theme. You can see the Frame change to SmokeyBlue theme.

When JTabbedPane is set to Top. I can see some space in between the tabs. You can observe in smokeyblueTop.png file. but the space between the tabs are not seen on other tab placement . You can observe in smokeyblueButtom.png , smokeyblueLeft.png &
smokeyblueRight.png files & smokeyblueTop.png . I have attached all the images files.

5) select Grand Canvon theme from 'Theme Preference frame'.
I observed that Top & buttom tab placement is normal (arrow button), but left & right tab placement is different arrow buttons are replaced with "+" & "-" button). I have attached two image files. In GrandCanyonDisable.PNG you can see the disabled button is having a arrow as the button label. In GrandCanyonEnable.PNG , you can see the enabled buttonn is having a '+' as the buttonlabel.

6) Select LargePrint theme from 'Theme Preference frame'.
I have observed that Top & buttom tab placement is normal ,but the arrow button are very small . when compared with left & right tab placement. This can be observed with other themes also.

I tested this with mustang b71 to b76 & its reproducable.