There is no a shorter line of a different color indicate in the column

Testsuite:Swing Manual
Test name(s):Swing_DnD/Manual/JTableTest
Product(s) tested: JDK11.0.1b04(64bit)
OS/architecture: ubuntu18.04-x64

Actual results:
Scenario:3
step2:There is no a shorter line of a different color indicate in the column in GTK LookAndFeel.refer to JTable-ubuntu18.04-x64.jpg.
The correct display refer to JTable-ubuntu18.04-x64-jdk11b06.jpg

Scenario:4
step3:There is no a shorter line of a different color indicate in the row in GTK LookAndFeel.

Verification:
JDK 10b46 on the same Platform:Passed
JDK 11b02 on the same Platform:Passed
JDK 11b06 on the same Platform:Passed
JDK 11b07 on the same Platform:Failed

JDK 11b06 on ubuntu16.04-x64:Passed