RFR: 8280020: Underline and line-through not straight in WebView

[Jay Bhaskar]

Issue: The end point of  line in drawLinesForText , add thickness to the endPoint.y(). In this case origin which is start point and the end point would not be same, and line would be drawn not straight.
Solution: Do not add thickness to the y position of end point of line.
Start Point(x,y) ----------End Point(x + width, 0)

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Commit messages:
 - 8280020: Underline and line-through not straight in WebView

Changes: https://git.openjdk.java.net/jfx/pull/731/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jfx&pr=731&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8280020
  Stats: 64 lines in 2 files changed: 63 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jfx/pull/731.diff
  Fetch: git fetch https://git.openjdk.java.net/jfx pull/731/head:pull/731

PR: https://git.openjdk.java.net/jfx/pull/731