8213781: web page background renders blue in JEditorPane

[TheMangovnik]

Backport of JDK-8213781 - web page background renders blue in JEditorPane

Fixing JEditorPane that for some webpages renders the background blue instead white. E.g. http://www.google.com/

Clean backport.
Passed tier1 tests. Existing failures are the same as on the unpatched code, they are unrelated.
Passed gtests.

GH Actions are passing except 4 macos x64 tests with TransportTimeoutException:

• jdk/jshell/ExceptionMessageTest
• jdk/jshell/JdiFailingLaunchExecutionControlTest
• jdk/jshell/JdiFailingListenExecutionControlTest
• jdk/jshell/JdiHangingLaunchExecutionControlTest

---

Progress

• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• JDK-8213781 needs maintainer approval
• JDK-4895924 needs maintainer approval

Error

 ⚠️ OCA signatory status must be verified

Warning

 ⚠️ Found leading lowercase letter in issue title for 8213781: web page background renders blue in JEditorPane

Issues

• JDK-8213781: web page background renders blue in JEditorPane (Bug - P3)
• JDK-4895924: Strings in format #rgb not handled by Color.decode() (affects CSS / Swing) (Bug - P4)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk11u-dev.git pull/3118/head:pull/3118
$ git checkout pull/3118

Update a local copy of the PR:
$ git checkout pull/3118
$ git pull https://git.openjdk.org/jdk11u-dev.git pull/3118/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 3118

View PR using the GUI difftool:
$ git pr show -t 3118

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk11u-dev/pull/3118.diff

[bridgekeeper]

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[openjdk]

❗ This change is not yet ready to be integrated.
See the Progress checklist in the description for automated requirements.

[openjdk]

This backport pull request has now been updated with issues from the original commit.