<Swing Dev> RFR: 4916923: In MetalRootPaneUI, MetalRootLayout does not correctly calculate minimumsize

[Sergey Bylokhov]

The typo in the MetalRootLayout is fixed. The tpWidth was replaced by the tpHeight for height calculation.

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Commit messages:
 - Initial fix

Changes: https://git.openjdk.java.net/jdk/pull/1155/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=1155&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-4916923
  Stats: 126 lines in 2 files changed: 117 ins; 0 del; 9 mod
  Patch: https://git.openjdk.java.net/jdk/pull/1155.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/1155/head:pull/1155

PR: https://git.openjdk.java.net/jdk/pull/1155