[jdk11u-dev] RFR: 8210047: some pages contain content outside of landmark region

[psoujany]

Backport of 8210047: some pages contain content outside of landmark region 

OpenJDK Bug : https://bugs.openjdk.org/browse/JDK-8210047

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Commit messages:
 - Fixed testcase failure
 - Backport a17816f881fadca8dc3bfd49458445873ae762cd

Changes: https://git.openjdk.org/jdk11u-dev/pull/1320/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk11u-dev&pr=1320&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8210047
  Stats: 501 lines in 12 files changed: 277 ins; 90 del; 134 mod
  Patch: https://git.openjdk.org/jdk11u-dev/pull/1320.diff
  Fetch: git fetch https://git.openjdk.org/jdk11u-dev pull/1320/head:pull/1320

PR: https://git.openjdk.org/jdk11u-dev/pull/1320